Bell's Theorem

Reply to tim wood

Hey Tim. It's good to hear from you. I've tried to figure out Bell's Theorem before with little success. I read your post and was still lost. I downloaded the Scientific American article to read.

The one thing that is really shocking is remembering that SA used to be a serious science magazine before it tried to make itself into another Discover or Popular Science. Not that that there's anything wrong with them, but SA used to be hard to read.

Reply to tim wood I think this is well-articulated even though I'm still not sure that I understand Bell's Inequality. So the sin^2 rule does not adhere under 45 degrees. Why is this a problem?

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Quoting tim wood

and that the particle-pair comes from an original single particle with spin zero

This part is incorrect. The original particle does not have a known spin, zero or otherwise. It is simply a thing not measured.
Quoting tim wood

The sum of the angular momentum of the two must then always be zero.

The particle does not have angular momentum. Spin in quantum theory is not a measurement of its rotation, a classical concept meaningful only to something with extension. It just means that they send the particle through a pair of charged plates and it is deflected one way or the other, never not at all, and always the same magnitude of deflection. This has been dubbed 'spin', but the word has nothing to do with the classical meaning of the word.

Quoting tim wood

It is a simple step to assume that before the measurement, the particle really has a determinate spin value that the detector measures.

That assumption should not be made. I'm pretty sure it can be falsified. It's a counterfactual assumption, and I'm not sure how counterfactual interpretations describe the state before measurement.

The rest of the post seems to run with this assumption, and thus diverges from what Bell shows. I'm no huge expert, and could not exactly explain what Bell shows other than the fact that it cannot be explained with any classic model. I mean, otherwise you can treat entangled pairs as a pair of coins facing in unknown but exactly opposite directions, and the 'spin measure' is just a camera oriented a certain direction relative to the coin which must, if the cameras are aligned the same way, read heads on one and tails on the other (and nothing else, not 'edge', not 'barely heads, damn it's almost edge and hard to read'). But that model fails with entangled particle behavior.

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Reply to tim wood Hi Tim - here's a rather good video presentation on the topic by Jim Baggott, whom I think is a respectable physics author and commentator. This was the presentation he gave at the launch of his latest book, and has a graphic overview of the inequality experiments. (I've attempted to queue the video to the start of the preceeding section which explains the context).



Helped me understand it!

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If you really want to understand Bell's theorem, you should visit a science forum Tim Wood. The terminology like "spin" is often misconstrued as an English equivalent. Often times words that sound like English are used as placeholders for deep mathematical and scientific concepts. At this level, everything is math with an often poor attempt to convert it into language. Only someone with a very clear scientific background would be qualified to speak with on this. Layman's understanding of quantum theories are often woefully inadequate and misunderstood.

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Quoting tim wood

Indeed! But I will quibble with you. In what sense do you suppose I do not understand the theorem, against what I do claim to understand about it?

Oh, my point was not that you do or do not understand the theory. You may very well have full mastery of it. I don't pretend to. I'm just noting that if you want to be assured of such I'm sure a scientist is going to be able to give you affirmation and/or enhance your understanding more than us philosophers. :)

Quoting tim wood

So you have a mathematical expression of a limit, and a mathematical description that accurately predicts the actual outcomes, and they're inconsistent with each other. And alas, there's no more than that to it.

Sorry it took me so long to get back to you. I read the SA article and a book called "What is Real" by Adam Becker recommended to me by @Count Timothy von Icarus. I think you've laid it out correctly in your OP. After struggling with reading the argument, one section of text allowed me to simplify things without necessarily understanding the details:

Quoting Scientific American

The Bell inequality constitutes an explicit prediction of the outcome of an experiment. The rules of quantum mechanics can be employed to predict the results of the same experiment. I shall not give the details of how the prediction is derived from the mathematical formalism of the quantum theory; it can be stated, however, that the procedure is completely explicit and is objective in the sense that anyone applying the rules correctly will get the same result. Surprisingly, the predictions of quantum mechanics differ from those of the local realistic theories. In particular, quantum mechanics predicts that for some choices of the axes A, B and C the Bell inequality is violated, so that there are more A+ B+ pairs of protons than there are A+C+ and B+ C+ pairs combined. Thus local realistic theories and quantum mechanics are in direct conflict.

Here's my simplified understanding:

• The Bell inequalities are calculated based on standard classical probability theory
• Their applicability is based on three assumptions - 1) the phenomena in question actually exist 2) induction works and 3) locality - i.e. things can only effect other things at the speed of light.
• You can use quantum mechanics to calculate the probabilities and you get different answers than classical probability theory.
• Experiments show that the quantum probabilities are correct.
• Therefore, looks like locality loses.

Quoting tim wood

And certainly not like the spin of a billiard ball or a basketball. My own opinion is that both spin and entanglement are defined as a kind of behavior of particles. I.e., if they behave that way, then they have spin and are entangled, and if they have spin and are entangled then they behave that way. I am unaware of anything more substantive than that, though I'm sure more is said.

I think there's more to it than that. In my, limited, understanding, when they're figuring out the total angular momentum of a hydrogen atom, they add the spin angular momentum of the electron with it's orbital angular momentum. So saying that spin is "not really" angular momentum misses something.

Quoting tim wood

the popular explanations of things just seem always to leave out some critical step or detail.

Yes, popular explanations seem to get lost in the ooh, ahh of the phenomena. I have often found that going back to original sources can give insights, even if you can't follow the whole argument. I'm going to take a look at Bell's original paper and see what I find. That may take a while.

Quoting tim wood

The speed of light as speed limit is what is sacrificed, but with an interesting qualification: that the particles “communicate” instantaneously, but that no message can be sent using entanglement.

This confuses me. What does it mean that communication takes place instantaneously but no information can be transmitted? I would have thought that "communication" means the transfer of information. I have to do more reading.

Reply to T Clark

This confuses me. What does it mean that communication takes place instantaneously but no information can be transmitted? I would have thought that "communication" means the transfer of information. I have to do more reading

It's not you, it's a confusing solution that is invoked to save relativity's "speed limit." Non-locality suggests that causal influences can move faster than the speed of light (although there are other interpretations like retro-causality, superdeterminism, etc.). But relativity originally said that isn't possible. The theory is saved by a move whereby we say it is information that cannot move faster than light. Information of course has many definitions, but the one here is crafted with preserving the speed limit in mind.

Practically, you can't use this phenomenon to send messages faster than light.

But we already knew that relativity is not consistent with quantum mechanics, so this wasn't completely suprising. Einstein himself was deeply troubled by non-locality.

There are plenty of neat little experiments that punch tiny holes in "physical laws." You can perform a trick with cesium gas to get faster than light behavior. In some experiments conservation of mass/energy seems to be violated (open to interpretation) and in some phenomena we seem to have very short periods where conservation is out of wack (more accepted). Part of the hope for any sort of new big paradigm shift is that it will explain all the little oddities that pop up in a way that is more intuitive.

I think non-locality is just a case where it's more helpful to say "yes it's counter intuitive, cause seems to be instantaneous across distances" at least in terms of basic explanations.

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Quoting tim wood

I think it works like this: Alice is on earth and Bob on a spaceship near Arcturus about 37 light years' distant, monitoring his particle detector. Its bell rings and Bob sees that it registers "up." What information does that convey to him? Ans. none.

Let's take a classical situation. Alice takes a black and a white bead and puts each in a separate opaque box without looking at them. She sends one box in a rocket 37 light years away and keeps the other in a desk drawer. Bob gets the box 50 or so years later, opens it, sees a white bead, and knows that Alice has a black bead. How is that different from the situation you describe?

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Reply to tim wood

We have definitely gotten to the end of my competence and then gone on few extra lengths. I have some more reading and thinking to do. This was a useful conversation for me.

Quoting tim wood

Different because the respective spins are not limited to opposites.

"Spin" is a highly deficient concept. It is an attempt to represent non-dimensional, non-spatial activity which is understood to occur within the internal of a non-dimensional point (a somewhat incoherent idea), with a three-dimensional representation. So the property which is represented by "spin" is not adequately represented in this way, and restricting the possibilities to two opposites will ensure that the law of excluded middle is always violated.

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Reply to tim wood I've found this article to be the most straight forwardly comprehensible explanation of bells theorem

https://www.lesswrong.com/posts/AnHJX42C6r6deohTG/bell-s-theorem-no-epr-reality#:~:text=%22If%2C%20without%20in%20any%20way,corresponding%20to%20this%20physical%20quantity.%22

It took me a few reads and quite a lot of solitary thought to fully grok what this explanation is saying, but I can say with relative confidence that I understand Bells Theorem to some reasonable degree. I understand both what it is saying and why it is saying it.

Quoting tim wood

So you have a mathematical expression of a limit, and a mathematical description that accurately predicts the actual outcomes, and they're inconsistent with each other. And alas, there's no more than that to it.

I will say I think you've done bells theorem a little bit of a disservice here. The fundamental proof can maybe loosely be summed up like what you've said here, but exactly what it proves is far more interesting than this gives it credit, in my view. You've said the dry bit but left out why anybody cares - and the real reason is truly fascinating.

Reply to T Clark if you've tried and struggled to understand it, I definitely recommend at least one go of the above article. It took some effort but it really clarified everything for me.

Quoting flannel jesus

if you've tried and struggled to understand it, I definitely recommend at least one go of the above article. It took some effort but it really clarified everything for me.

Thanks. I took a look.

I'm not really confused about the mechanics of tests of the Bell inequality. If you do this and this, then this happens. Relatively straightforward. The implications of those results are a bit harder to get a grip on - What do they say about realism and locality? Where this all started for me was with the question whether or not the results of Bell inequality experiments have any implications for determining which interpretation of quantum mechanics is the correct one. As far as I can see, the results have nothing definitive to say about QM interpretations.

That leaves me where I started - if the different interpretations give the same results, they are equivalent. Any differences between them are metaphysics, not science. That will remain the case until someone can figure out how to test for differences between the interpretations. I predict, on the basis of my limited understanding, that it will not be possible.

Quoting T Clark

The implications of those results are a bit harder to get a grip on - What do they say about realism and locality?

Sure, I thought the article maybe did a good job at explaining that but perhaps it's not as explicit as it could be. I'm only a layman, but I do have what I consider to be a relatively compelling analogy, if you're interested.

Quoting flannel jesus

Sure, I thought the article maybe did a good job at explaining that but perhaps it's not as explicit as it could be. I'm only a layman, but I do have what I consider to be a relatively compelling analogy, if you're interested.

The article was fine. It did explain the Bell inequalities well. I also am very much a layman. Very, very much. That's why I have been struggling with the implications of QM once you get beyond the basic questions. Different expert sources give very different answers to the questions I am looking for answers to. Locality matters. It doesn't. Realism matters. It doesn't. All interpretations of QM are equivalent. They're not. Just because locality is violated, that doesn't mean that QM can be used to send information faster than the speed of light. It does.

Reply to T Clark well, if you're not interested in my long explanation of the implications of the results then, in short, what bells theorem proves is that we do in fact live in a quantum universe and not a classical one. Quantum measurements are indeterminate prior to measurement, genuinely and actually indeterminate rather than just a question that we don't yet have the answer to. Ontologically indeterminate, if you will. Bells theorem settles that question pretty cleanly, which is why it's so valuable in the history of quantum mechanics.

I can go into why at length but it doesn't look like you're asking for that.

Almost all experts are going to agree that you can't use qm to send information faster than light. Some people don't care about interpretations at all, they just care about qm as a tool to get predictions out of. Other people take the question of interpretations very seriously.

Quoting flannel jesus

Quantum measurements are indeterminate prior to measurement, genuinely and actually indeterminate rather than just a question that we don't yet have the answer to. Ontologically indeterminate, if you will. Bells theorem settles that question pretty cleanly, which is why it's so valuable in the history of quantum mechanics.

Except you'll find people who disagree with that. The whole many earth's interpretation was developed to address that issue. Reality is a metaphysical characteristic, not a scientific one.

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Quoting tim wood

"When certain elementary particles move through a magnetic field, they are deflected in a manner that suggests they have the properties of little magnets. In the classical world, a charged, spinning object has magnetic properties that are very much like those exhibited by these elementary particles. Physicists love analogies, so they described the elementary particles too in terms of their 'spin.'

"Unfortunately, the analogy breaks down, and we have come to realize that it is misleading to conjure up an image of the electron as a small spinning object. Instead we have learned simply to accept the observed fact that the electron is deflected by magnetic fields. If one insists on the image of a spinning object, then real paradoxes arise; unlike a tossed softball, for instance, the spin of an electron never changes, and it has only two possible orientations. In addition, the very notion that electrons and protons are solid 'objects' that can 'rotate' in space is itself difficult to sustain, given what we know about the rules of quantum mechanics. The term 'spin,' however, still remains."

Just as I said, the so-called "spin" is not a property of a particle at all. The 3-d geometrical representation which is called "spin" cannot be the property of a non-dimensional point.

Quoting tim wood

May I know what you were drinking before you wrote your post? I should like to try some for those occasions when I too would like to loosen my grip on reality.

As you've already indicated, we ought not focus on realism, so reality might be completely irrelevant to this subject. I believe that now might be the optimum time for you to go a ahead and loosen that grip on your assumed "reality". So, if you're interested in purchasing some of my special intelligence boosting juice, you'll need to send the money first, then I'll decide whether you're likely to benefit from it.

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Reply to T Clark Do you mean many worlds? Many worlds doesn't disagree with it at all. Many worlds actually very naturally fits in with my description (I should also clarify that a world, in Many Worlds, doesn't mean a planet like earth. )

Quoting tim wood

And I agree with brother Clark, here:
...the results have nothing definitive to say about QM interpretations.... Except you'll find people who disagree with that. The whole many earth's interpretation was developed to address that issue. Reality is a metaphysical characteristic, not a scientific one.
— T Clark

As to our living in a quantum universe, I buy that. But I accept that most of the effects are too small or too unlikely to matter much. Not impossible, just unlikely.

If you care to lay out your own interpretation, "compelling analogy," I'm a reader!

I will lay it out soon, because it's one of the most fascinating things I've ever tried to understand. For now let me just reiterate this:

The point of Bell's Theorem and the experiments that test it is to clarify if it's at all possible if we live in a world that's describable classically. You laid out some of the statistics that go into Bells Theorem, but in your first few posts I think you left out an explanation of why those statistics matter. That's what I'm focusing on here.

They matter because they prove with reasonable certainty that we live in a world that does not match up with classical assumptions.

T Clark said many people disagree with that and he brought up "many earths", which I assume to be many worlds - please correct me if I'm wrong. Many worlds is quantum mechanics. Many worlds is NOT classical. Many worlds also believes in indeterminate answers to measurement questions prior to measurement.

The classical idea is that any measurable property of a particle - momentum or position or spin - has a definite, objectively true answer even when you're not measuring it. If you send off a photon at t=1 and measure it at t=100, in classical mechanics that particle still has a singular, definite and true answer for any question you could ask of it at t=2 - 99. Just because you don't know the answer in classical mechanics doesn't mean there isn't one - there always is.

The inequalities in Bells Theorem are there to help us test if our universe is one where it's in fact true that we might live in a classical universe where those questions have singular, definite answers. Many Worlds does not involve singular definite answers to quantum questions, and the key to why is in the name, "many". Many Worlds takes the idea of superposition super-literally, and in many worlds any answer to a quantum question prior to measurement doesn't have a singular definite answer, it has MANY answers.

I'm going to try to take the time later to go over my analogy about why bells theorem says these questions can't have classical answers. I honestly love this topic so much. But I'll leave you with that for now.

Quoting tim wood

Maybe I'm misreading you, MU. It seems to me you're objecting to the use of the English word "spin" to refer to something meaningful to a technical user as a term of art. If that's the case, why?

Yes, you very much were misreading me. I was talking about the deficiencies of the concept which is labeled with the word "spin", as stated in the first sentence of my post: "'Spin' is a highly deficient concept." The choice of word to name the concept is irrelevant. All I can say is try rereading, and stay focused this time. That ought not be difficult because it's not a long post.

Reply to tim wood Reply to T Clark

This is the second time I've ever tried to describe at length what's so important and fascinating about Bell's Theorem, but my first time was a semi-failure (partly because I was trying to explain it to someone who rejected QM out of the gate, and didn't want to understand the maths and probabilities involved - which makes this scenario fundamentally different out of the gate, you guys seem to like QM and have some understanding of the probabilities involved), so this time I'm going to start again without using any of the material I wrote the first time. I'm going to probably be writing some shit you already know, but please bear with me. Also, sorry if this is a lot to read.

I think the best way to contextualize Bell's Theorem is to go back to the beginning, back to when QM was first being introduced to the physics community. I'm going to spin a little narrative that's perhaps not entirely true, but hopefully true enough, to set the stage for why Bell's Theorem was even thought up to begin with.

Before QM, all physical theories were what we now call "classical", including Relativity. I think of "classical" as almost being comparable to basic object-permanence. We all learn at some age that, if we put a book in our backpack and then close our backpack, we can (usually) expect to find it in our backpack later on. When we open up our backpack an hour later, we generally don't assume that the book just appeared there - we have a persistent conception of the world where, even when we weren't looking at the book, it was still in the backpack all the same. Classical Theories are object-permanence at the universal scale - every particle that exists always exists in a specific place at every moment in time, even when we're not looking at it. Our ignorance of where a particle is or how fast it's moving is just a fact about us, not a fact about the particle itself. The particle itself is always existing somewhere, and moving at some specific velocity, at every moment in time, regardless of our ignorance about it.

Then, Bohr, Planck, Heisenberg, Schrodinger and friends introduced QM to the world. They said that there are some properties of particles that, prior to measurement, we can't actually tell a Classical story about. If we shoot a particle at t=0, through a double slit for example, and measure where that particle landed at t=100, we might be tempted to ask the question "ok, so where was that particle at t=50?" If the world worked classically, then there would be an objectively true answer to that question - even if we as human beings couldn't find an answer. If we can't find an answer, that's just our own ignorance, but there still *is* an answer. QM said, actually, there *is not* an answer. Or at least, not a *singular, definite answer* -- that's the phrasing I like to use. Prior to measurement, some of these properties of things like Photons and Electrons do not in fact have singular definite answers - not even to God. If God himself were to peer into the universe and look at that particle at t=50, he wouldn't have a singular definite answer to the question "where was that particle?" (Please note that I'm using God as a narrative tool, I'm not a theist. "God" is just a stand in for the idea of some external entity who could, in principle, know the world as it really is - could answer any question about any system without disturbing that system).

Shortly after, Einstein and friends produced the EPR paper. In short, they fundamentally disagreed that the QM vision of the world was true. They said, no, if we don't know where a particle is, or its velocity, or any other measurable property of that particle, that's just a matter of personal ignorance. Quantum indeterminacy is not a real feature of reality, it's just a measure of the things we don't know. And they came up with a theoretical class of experiment to demonstrate why. They said (again, I'm using some artistic license here, this isn't exactly how it happened) -- imagine we have a pair of particles that we've arranged to have a correlated state in some measurable property. Now, we have one particle flying east and one flying west, we haven't measured this property yet so according to QM this property doesn't have a singular definite answer yet. After, say, a second we measure the particle flying west -- if their properties are correlated, as by the experimental design, then that means at the moment we measure the West particle, the East particle must also suddenly and immediately have an answer as to what it will be measured as as well, despite being 2 light-seconds away. This thought experiment, as far as I know, is the first time the idea of "entanglement", as we now call it, was discussed at length. Einstein referred to the idea that measuring one particle could affect its entangled paired particle immediately as "spooky action at a distance". The idea of instantaneous causality across space went against every intuition about physics Einstein had - it went directly against intuitive notions of Causality and his own Relativity. After all, if cause-and-effect can happen immediately across distances, that creates a real problem for the idea of Relativity of Simultaneity (please ask if you want more detail on this and why it was such a problem).

So, what we have here is 2 competing ideas: 1. the classical take of Einstein via the EPR paper, that us not knowing what a property would be measured as is just a statement about our own ignorance, not a statement about reality, and 2. the QM take, that these properties are not just something WE are ignorant about - God himself wouldn't have an answer. There objectively is not an answer to these quantum questions prior to measurement. And the tricky part here is, how could you possibly tell? How could we tell what type of universe we live in? A classical one or a QM one? What experiment could tell us the difference between "I don't know this property of this particle" and "this property of this particle genuinely does not have a singular definite value"? On the surface, those two ideas - personal ignorance vs ontoloical lack of an answer in reality - seem experimentally indistinguishable.

THIS is where Bell's Theorem steps in. Bell ingeniously figured out a way to definitely tell us if we live in a world where a lack of an answer to quantum questions was because of personal ignorance, or if in fact QM was right and ontologically the answer to this quantum questions *cannot* in fact have a singular definite answer prior to measurement. This, to me, is why Bell's Theorem is so wonderfully beautiful, and so centrally important - it took us 40-odd years to finally find a way to settle the disagreement betweein Einstein and QM. Thank you, John Bell.

When the EPR paper came out, I'm not quite sure personally how they imagined setting up an entangled pair of particles, but by the time John Bell was approaching the question, I believe physicists had a good idea about this concept of "spin" - that you could create a pair of entangled particles where, due to the perservation of the quantum equivalent of "angular momentum", you could guarantee that one particle had the opposite spin of the other particle. I actually don't believe they had experimentally confirmed this could be done at this point, I think it was still theory when Bell came up with the idea, but nonetheless this is where we can start untangling the disagreement between Einstein and QM. What Bell discovered was, Quantum Mechanics predicts certain correlations of spins at varying degrees of measurement, and the exact correlations it predicts are *incompatible* with Einstein's view of the world. If you read the wiki page on Bell's Theorem, you'll see it referred to as "local hidden variables" - local hidden variables, Bell figured out, could not (at least not without some weird loopholes) explain the statistical results that QM predicts. So let's go into why and what that means.

First, let's just talk about what you alread know: in a Bell Test, they create a pair of particles that have entangled spin. One of them goes left, one of them goes right. If you measure their spin along the same axis, if they're properly entangled then one spin will be up and one will always be down. If you measure them at a different angle, however, the statistics start to differ a little bit.

Here's where I introduce the "analogy" I've been touting prior. Local Hidden Variables and entanglement. I'm absolutely certain I'm oversimplifying this but I think the simplification I'm going to present is useful at the very least, so here it goes: Local Hidden Variables theories are basically Classical theories, which is to say they match this idea of Object Permanence I talked about - regardless of our own ignorance, every property of a particle has a singular definite value at all moments in time. Now the idea that two particles could have some correlated value isn't itself incompatible with Classical theories, so here's the first layer of the analogy: A person called FJ (me) is offering a service online. You send me 2 addresses and a dollar, and I'll send an envolope with a piece of paper in it to each address. The service is very simple: to one address I'll send an envelope with a red piece of paper inside, and to the other addrss I'll send an envelope with a green piece of paper inside. This is "classical entanglement", aka the Local Hidden Variables view of entanglement. You purchase my services and send me your address and T.Clark's address, and when you get your envelope you open it and you see a Green piece of paper. You have *immediately and instantaneously* learned information about the envelope heading to T.Clark's house. You know for a fact that the paper going to him is Red, regardless of the fact that it hasn't been measured yet. This isn't magic and it's not quantum, this is the classical view of entanglement.

So, the analogy is a "particle" is an envelope, and a "measurement" is opening the envelope here, and in a classical system, there's nothing weird or strange about the idea that the contents of one envelope could be perfectly correlated with the contents of another envelope, right? I hope that all makes sense. We consider it classical because, even if you opened the envelope, say, 24 hours after I mailed it off, you could reasonably ask the question "what color was the paper in this envlope 12 hours after it was sent?" and, common sense says, it was green when you opened it and so it was green 12 hours before you opened it as well. And 23 hours before you opened it. And 1 hour before you opened it. When you opened this envelope, you weren't generating some new fact about the color of the paper, you were discovering a fact that was true the whole time - that's what makes it classical. Complete object permanence. Objective facts regardless of your ignorance.

I send you an email a few days later letting you know I'm offering a more advanced service. I'm offering to send the 2 envelopes with a paper inside, same as before, but this time I'm going to write a number on each one. On the first paper I write a number from 0 - 359 - let's call this number X. On the second paper, I'm going to write whatever this formula outputs: (X + 180) MOD 360. So, whatever the first number is, the second number is 180 degrees rotated from the first number. If the first number is 1, the second number is 181. If the first number is 90, the second number is 270. If the first number is 320, the second number is (320 + 180) mod 360 which is 140. Now this service I'm offering is *almost* directly comparable to the experiment in a Bell test. The only thing you have left to do to make it actually comparable to a Bell test is devise a *measurement scheme* that makes it similar to a Bell test, which is actually remarkably easy.

Like before, you ask me to send one envelope to your house and one to T.Clark's house. You've agreed with T.Clark for the first round to measure every number received according to this scheme: If the number is between 0 and 180 (including 0, not including 180), you record an UP on your spreadsheet, and if it's from 180 - 360 (including 180, not including 360 aka 0) you'll record a DOWN on your spreadsheet.

So, you run the test 1000 times, say, and after you compare your spreadsheet with T.Clark's spreadsheet, you're completely unsurprised to discover that every time you've recorded UP, he's recorded DOWN, and vice versa. Again, this is just basic, classical entanglement. These envelopes are classical envelopes, filled with classical paper, written on with classical pen. You might measure a particle as UP after you receive it, but the number was already written in pen long before you received it. Nothing weird here.

But meanwhile you and T.Clark have also set up some entangled quantum photons to arrive at your houses, and you're measuring their spins, and you've noticed with the entangled particles that when you run the test above, measuring their spin at the same angle, you get the same results as the envelope experiment - every result you see as UP, T.Clark sees as DOWN, and vice versa. So in this case, our classical experiment is looking a lot like our quantum experiment.

So, you and T.Clark start changing the experiment up, and you start doing a proper Bell test. Some of the time, you measure a particle at, say, 0° and he measures it at 20°. Some of the time, you measure a particle at 20° and he measures it at 40°. And some of the time, you measure a particle at 0° and he measures it at 40°. {0° above means UP if it's [0-180) and DOWN if it's [180-360), 40° means UP if it's [40-220)}. You both record your ups and downs now, and you discover the following set of facts:

When you're measuring 0° and he's doing 20°, you BOTH record UP 5.8% of the time (as in, 5.8% of the time yours and his both register UP for the same run).

When you're measuring 20° and he's doing 40°, you BOTH record UP 5.8% of the time.

When you're measuring 0° and he's doing 40°, you BOTH record UP 20.7% of the time.

Now, you decide to run the same sort of tests using FJ's mailing service just to see what the results are, to compare your quantum measurements to a classical system. Here's what you get.

When you're measuring 0° and he's doing 20°, you BOTH record UP 5.55...% of the time.

When you're measuring 20° and he's doing 40°, you BOTH record UP 5.55...% of the time.

When you're measuring 0° and he's doing 40°, you BOTH record UP 11.111...% of the time.

You notice this, tim, and you have a little intuition: you think that in my classical mailing service, it's actually impossible for my classical mailing service to produce the 5.8, 5.8, 20.7% statistics from the quantum tests. You think that it might be the case that the 0-20 and 20-40 statistics might have to add up to the 0-40 statistics, but maybe you can't quite explain why yet. You intuitively think there's no way for me to recreate that distrubituion. So, you tell T.Clark and he disagrees (I'm sure you wouldn't actually disagree, mr Clark, it's just a story). So you make a bet - you tell T.Clark that HE can call up and tell me (FJ, the mailing man) exactly what numbers to put in the envelopes, BUT you, tim, YOU get to decide how they're going to be measured (0 and 0, 0 and 20, 20 and 40 or 0 and 40), and you decide that 12 hours after the envelope is sent off, so T.Clark and FJ have no way of knowing which angles you're going to measure them at. So the bet is this: under those conditions, can T.Clark and FJ create a scheme that will make it so that at 0 and 0, all the result are opposite, at 0 and 20 they're both up 5.8% of the time, and 20 and 40 they're both up 5.8% of the time, and at 0 and 40 they're both up 20.7% of the time?

So, at this stage, what do you think? Can FJ and T.Clark devise any system of sending these letters to you in the conditions given? Is there any strategy at all they could take to produce these distributions reliably?

Bell's Theorem says there isn't. The only out that I know of, the only loop hole, is that if T.Clark and FJ already know ahead of time how you're going to be measuring them, THEN FJ and T.Clark can conspire to rig the results (this is essentially what Superdeterminism means, it means that the mechanism creating the spin values knows ahead of time how they're going to be measured and has conspired to give the results QM predicts). But I've worded it such that that loophole is closed - "BUT you, tim, YOU get to decide how they're going to be measured, and you decide that 12 hours after the envelope is sent off" - so they can't cheat in the superdeterministic way.

If there's no way for FJ's classical mailing system to produce the statistical outputs that QM predicts - that 5.8% and 20.7% numbers - then that means we can possibly prove that we don't live in a classical world.

So what do you think? Can FJ and T.Clark devise such a system, so that the mailing system can output those numbers? Can you devise such a system?

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Quoting tim wood

Many Worlds takes the idea of superposition super-literally, and in many worlds any answer to a quantum question prior to measurement doesn't have a singular definite answer, it has MANY answers.
— flannel jesus
Which is not the claim that answers impossible in one world are possible in others, or is it? In some worlds do I murder my own parents before I am born? My understanding of many-worlds is that whole entire complete universes flash into and out of existence at every juncture of every instant of the existence of every thing, and that seems unlikely.

The many worlds thing was an aside, and not at all necessary or required to understand everything I'm saying about bells theorem. The stuff I'm saying about bells theorem is entirely agnostic about which interpretation of quantum mechanics is correct.

Quoting tim wood

So I conclude that QM, in sum, is a model that highlights deficiencies in classical physics but that does not replace classical physics, or, rather instead, becomes it. That is, that QM perfected will be seen to be a classical theory that is an advance on and refinement of current classical theory, in a way as relativity refines and advances on Newtonian physics.

I suppose you're free to conclude that but that's certainly not my understanding, or I dare say the understanding of physicists who study qm. My entire post was getting at the point that QM is entirely at odds with some classical assumptions, and bells theorem and the experiments that test it go on to show that the classical assumptions cannot hold, they don't match experimental results.

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Quoting tim wood

That is, measurements on single particles allow for a classical interpretation, and on entangled particles, not.

Sorry for multiple responses, maybe I should post these together. In any case, this bit is probably not generally agreeable either. There are other single-particle experiments which are hard to explain with classical mechanics and start making more sense when modelled with quantum mechanics. The double slit experiment is one. The Mach zender interferometer experiment is another.

Reply to tim wood I really don't know why you're talking about nothing happening Vs something happening. There's nothing in my understanding of any of this that leads me to think that's a debate physicists are now or have ever had.

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Reply to tim wood Are those the two options? Well they clearly fail for a reason, I think. And the reason is, the world is not classical. That's why our experimental results show correlations that are predicted by qm, and not explainable by classical means

Are you asking me why they're not explainable by classical means?

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Reply to tim wood by determinate do you mean deterministic? Or do you mean something else, like "what's actually happening under the hood still involves objective facts"?

QM will always be indeterminate in the sense I've said above - that even God himself doesn't have a singular answer to a question like "where was this particle at t=50" - that's the nature of qm. That doesn't mean there aren't objectively true facts, however, even at t=50. It just means those objectively true facts aren't the type of facts we're used to asking about, they aren't the type of answers we're used to receiving. You have to bend your mind to accept different kinds of answers than that.

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No, this whole line of questioning doesn't even make sense to me. I don't understand why you're even asking it. Quantum indeterminacy doesn't mean everything happens for no reason, and I've never claimed it does. Your questions along this line seem nonsensical to me.

I'm also still concerned that you're treating the words indeterminate and indeterministic as interchangable.

Quoting flannel jesus

Many worlds doesn't disagree with it at all.

I didn't say that the two approaches disagreed, I said that one of the reasons many worlds is appealing is that some people see it as addressing the claim that quantum phenomena are "ontologically indeterminant."

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Quoting flannel jesus

They matter because they prove with reasonable certainty that we live in a world that does not match up with classical assumptions.

T Clark said many people disagree with that and he brought up "many earths", which I assume to be many worlds - please correct me if I'm wrong. Many worlds is quantum mechanics. Many worlds is NOT classical. Many worlds also believes in indeterminate answers to measurement questions prior to measurement.

You keep misstating my position. It's frustrating. I never wrote and I don't believe that the subatomic world is describable in terms of classical physics. I said I don't see that quantum mechanics rules out realism. Quantum mechanical phenomena behave differently than classical phenomena, but that doesn't mean they're not real.

Quoting flannel jesus

The inequalities in Bells Theorem are there to help us test if our universe is one where it's in fact true that we might live in a classical universe where those questions have singular, definite answers.

In my understanding, this is not true. It is your interpretation, not mine and probably not Bell's. The inequalities are not "there to help us," they describe phenomena at very small scales.

Quoting flannel jesus

to explain it to someone who rejected QM out of the gate, and didn't want to understand the maths and probabilities involved

Are you talking about me again? If so, stop misrepresenting what I wrote.

Reply to tim wood I don't know why you keep saying this "no reason" stuff. I've never indicated that things happen for no reason

Reply to T Clark no, not about you, I was referring to something that happened on another forum possibly around a year ago.

Reply to T Clark my mistake. Your post said some disagree, and then you brought up many worlds in a way that sounded like you think many worlds is an example of disagreement.

Quoting flannel jesus

?T Clark my mistake. Your post said some disagree, and then you brought up many worlds in a way that sounded like you think many worlds is an example of disagreement.

Quoting T Clark

The inequalities in Bells Theorem are there to help us test if our universe is one where it's in fact true that we might live in a classical universe where those questions have singular, definite answers.
— flannel jesus

In my understanding, this is not true. It is your interpretation, not mine and probably not Bell's. The inequalities are not "there to help us," they describe phenomena at very small scales.

The Wikipedia page on bells theorem states explicitly - Bell's theorem is a term encompassing a number of closely related results in physics, all of which determine that quantum mechanics is incompatible with local hidden-variable theories. The quote of mine is just rewording that, where I replace "local hidden variable theories" with the phrase "classical universe where those questions have singular, definite answers." Those phrases may not be perfectly interchangeable, but they are close to interchangeable. Despite your misgivings, I have read enough about bells theorem to be relatively confident that what I said is at least loosely close to the way it was intended by bell and understood by modern physicists.

Reply to T Clark in addition to the above quote from Wikipedia, please see this quote from the Stanford article on bells theorem

https://plato.stanford.edu/entries/bell-theorem/

Finally, in 2015, experiments were performed that demonstrated violation of Bell inequalities with these loopholes blocked. This has consequences for our physical worldview; the conditions that entail Bell inequalities are, arguably, an integral part of the physical worldview that was accepted prior to the advent of quantum mechanics. If one accepts the lessons of the experimental results, then some one or other of these conditions must be rejected.

If one accepts the experimental results, then some of the conditions that were integral to the physical world view accepted prior to quantum mechanics must be rejected. The physical world view prior to quantum mechanics was what I've been referring to as "classical". I do believe Stanford is saying, in different wording, the same thing I'm saying : the experimental results we get from the tests of bells theorem tell us that we, in fact, do not live in a classical world.

I'm not pulling this interpretation of bells theorem out of my ass. It is possible, however, that I'm terrible at explaining myself or defending myself

Reply to T Clark Sorry to bombard, but here's another quote from the same Stanford article:

7. Significance for Quantum Information Theory
The set-up envisaged in the proof of Bell’s theorem highlights a striking prediction of quantum theory, namely, long-distance entanglement, and experimental tests of the Bell inequalities provide convincing evidence that it is a feature of reality. Moreover, Bell’s theorem reveals that the entanglement-based correlations predicted by quantum mechanics are strikingly different from the sort of locally explicable correlations familiar in a classical context.

"Bell’s theorem reveals that the entanglement-based correlations predicted by quantum mechanics are strikingly different from the sort of locally explicable correlations familiar in a classical context." This sounds a lot like what I've been saying.

Quoting flannel jesus

The quote of mine is just rewording that, where I replace "local hidden variable theories" with the phrase "classical universe where those questions have singular, definite answers." Those phrases may not be perfectly interchangeable, but they are close to interchangeable.

I don't see how the two phrases are interchangeable at all.

Quoting T Clark

I don't see how the two phrases are interchangeable at all.

Does the second quote from stanford lend any clarity in that direction for you at all?

Bell’s theorem reveals that the entanglement-based correlations predicted by quantum mechanics are strikingly different from the sort of locally explicable correlations familiar in a classical context.

Quoting tim wood

It seems you fail to distinguish between spin and "spin." Forget the ordinary English word "spin". And for clarity's sake just for you in this post let's call the other spxn. Let's suppose what is actually the case, that certain people use the term that we call here spxn to represent a set of ideas that they have collectively, and that they can convey to each other by speaking and writing the word spxn. In as much as I am not one of those people, I will leave to them the choice of their own words for their own use; and I (shall) assume the the word is efficacious when used by them among themselves. So much for the word

It's not quite correct to ask for such a separation in the use of "spin", because no matter how you look at it spin is still a type of angular momentum, and this is a vector concept. The point I was making is that such dimensional concepts are not adequate for explaining the properties of particles which are assumed to be non-dimensional. Read the following from Wikipedia:

[quote=Wikipedia: Angular momentum]The three-dimensional angular momentum for a point particle is classically represented as a pseudovector r × p, the cross product of the particle's position vector r (relative to some origin) and its momentum vector; the latter is p = mv in Newtonian mechanics. Unlike linear momentum, angular momentum depends on where this origin is chosen, since the particle's position is measured from it.[/quote]

Notice, "pseudovector", because the principles of classical 3-d vectors do not hold for these particles. So consider Flannel Jesus' explanation. The existence of the particle cannot be validated during the entire time between t1 and t100. It is only validated at these two time points through measurement of those properties like "spin". However, these concepts which make up those supposed properties are not adequate to measure what is really there at that time. So, since the existence of the particle is only known by determining these properties, at those two times, and these properties do not even accurately represent what is there at those times, and the indication is that there is no determinable particle between those times, then why should we even think that there is any particle at any time whatsoever? These dimensional concept like "spin" are misleading us.

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Quoting flannel jesus

Bell’s theorem reveals that the entanglement-based correlations predicted by quantum mechanics are strikingly different from the sort of locally explicable correlations familiar in a classical context.

I understand that phenomena at atomic and subatomic scales behave differently than those at human scale. It is common that phenomena at different scales behave differently. Superconductivity manifests at temperatures near absolute zero but is not seen at room temperature. Relativistic effects manifest at speeds near the speed of light but are not seen at slower speeds. What's the big deal?

Quoting tim wood

"Validated"? I'm not sure this will be a useful discussion. It seems you want to commit the fallacy of, "Because I do not know, I know."

And if you were honest about it, you'd have taken note of the quoted remark above that make clear that the term - and the concepts - of spin are problematic,

No, I'm being honest, it's not a matter of "because I do not know...". I'm going by what flannel jesus said:

Quoting flannel jesus

Then, Bohr, Planck, Heisenberg, Schrodinger and friends introduced QM to the world. They said that there are some properties of particles that, prior to measurement, we can't actually tell a Classical story about. If we shoot a particle at t=0, through a double slit for example, and measure where that particle landed at t=100, we might be tempted to ask the question "ok, so where was that particle at t=50?" If the world worked classically, then there would be an objectively true answer to that question - even if we as human beings couldn't find an answer. If we can't find an answer, that's just our own ignorance, but there still *is* an answer. QM said, actually, there *is not* an answer. Or at least, not a *singular, definite answer* -- that's the phrasing I like to use. Prior to measurement, some of these properties of things like Photons and Electrons do not in fact have singular definite answers - not even to God. If God himself were to peer into the universe and look at that particle at t=50, he wouldn't have a singular definite answer to the question "where was that particle?" (Please note that I'm using God as a narrative tool, I'm not a theist. "God" is just a stand in for the idea of some external entity who could, in principle, know the world as it really is - could answer any question about any system without disturbing that system).

If the particle has no location at t50, then there is no particle at that time. Why is that not obvious to you tim?. There is no such thing as an object like a particle, without a spatial location. To accept otherwise is to venture into a world filled with magic.

Quoting tim wood

The detectors reliably and consistently measure something, called in this case spin - and it is at the moment irrelevant as to what spin is - and this spin deemed to be an aspect or quality of the particle itself.

Let's be more precise with our terminology, let's just say that the detectors detect something. Because there is uncertainty between the relation of position and momentum, we ought not even call this a "measurement". Due to the uncertainty relation, we cannot accurately say what is being measured, so it's a stretch to even say it is a measurement.

And, because of this uncertainty, the concept referred to by "spin" is not a property of anything at all. It's just a mathematical way of describing what the detector detected. So if we go ahead and look at your proposition 'This spin is an aspect or quality of the particle itself', we must designate it as a false and misleading proposition. The detector is not really detecting any properties of any particles. It is detecting something which is called "spin", but the concept associated with this term in no way is an accurate representation of what is actually being detected

Quoting tim wood

Denial of the particle having this spin except when it is measured begs the question as to how the particle knows it's being measured and reacts, and what, exactly, triggers that knowledge and reaction, not to speak of the time that all takes.

Failure to recognize that there is not even a particle being detected, and that these dimensional-based (classical-based) concepts such as "spin" are woefully inadequate for describing the wave activity being detected, is misleading you here. I am not denying that the particle has "spin", I am denying that there is a particle. The concept, "spin", which refers to what is detected, does not properly represent what is actually detected, therefore the existence of the thing (particle) which is assumed to have that property is not substantiated (if you do not like "validated").

Reply to T Clark What's the big deal? Well, some dudes won the Nobel prize in 2022 in large part because of their experiments confirming violation of bells inequality, so the scientific establishment at large seems to understand that it's a big deal. I think it's pretty clear that the big deal is, violations of bells inequalities are unreproducible using classical means, and I believe that's what the Stanford quote is saying. I think it's a pretty big deal. You are of course under no obligation to think it's a big deal. You're under no obligation to be interested in QM at all. I, personally, think it's fascinating, mind blowing even.

Here's some other people across the internet who are apparently understanding it in similar ways to me:

https://physics.stackexchange.com/questions/732672/any-bell-experiments-showing-inequality-violations-in-purely-classical-systems-a

https://www.quora.com/In-simple-layman-s-terms-what-does-it-mean-to-violate-Bells-inequality-In-experiments-that-are-actually-done-how-is-the-violation-detected#:~:text=Short%20answer%3A,repetitions%20of%20a%20simple%20experiment.

(On the above link, see the second answer by amit)

https://physics.stackexchange.com/questions/370386/is-bells-inequality-always-violated

https://physics.stackexchange.com/questions/139880/can-bells-inequality-violation-be-explained-by-the-will-of-the-scientist-someho

https://physics.stackexchange.com/questions/675344/what-is-it-about-quantum-entanglement-that-cannot-be-explained-classically?noredirect=1&lq=1

Of course, all of these links do not prove I am correct. I'm not trying to prove I'm correct. I am trying to give you some signals that this isn't just some silly misunderstanding of bells theorem that I've invented. You may disagree that it is the correct way to understand bells Theorem, but I'm not pulling this understanding out of no where. I'm not just some silly goober inventing new nonsensical ways of understanding experiments. I believe my understanding is in fact the intended understanding.

Quoting flannel jesus

What's the big deal?... I'm not just some silly goober inventing new nonsensical ways of understanding experiments. I believe my understanding is in fact the intended understanding.

You have misrepresented the things I wrote in every response you've made to my posts in this discussion and I'm tired of it. What I'm saying is not that hard to understand and it doesn't contradict Bell's theorem or call into question the results of experimental testing or it's scientific importance.

I'm all done.

Reply to T Clark It was never my intention to deliberately misunderstand anything you wrote. The only misunderstanding you've explicitly pointed out so far is that bit about Many Worlds. If you don't want to explicitly lay out the things you think I'm misunderstanding, then of course I cannot correct my misunderstanding.

I don't even know what you mean about how what you're saying doesn't contradict bells theorem. As far as I can tell, this whole conversation lately has just been you telling me I'm misinterpreting bells theorem. I've never said your ideas contradict bells theorem, because I don't even know what your ideas are.

But if you're done, then see ya I guess.

Quoting flannel jesus

this whole conversation lately has just been you telling me I'm misinterpreting bells theorem.

I never said you misinterpreted Bell's theorem, I said you misrepresented what I wrote. Which you've just done again. I don't think our misunderstanding each other is intentional. It certainly isn't on my side.

Let's try this discussion again the next time it comes around. We're not getting anywhere here.

Reply to T Clark After I gave my understanding of bells theorem, your initial response was this:

In my understanding, this is not true. It is your interpretation, not mine and probably not Bell's. The inequalities are not "there to help us," they describe phenomena at very small scales.

And ever since that post, it's been me trying to defend what I've said about bells theorem. If that response you gave isn't you saying I've misinterpreted bells theorem, what is it? What else could it possibly be?

It's okay for you to think I've misinterpreted it. I'm here to talk about ideas, I'm not afraid of disagreement. I'm clearly willing to put in some energy and work to try to understand things properly, and defend my understanding when I think I've got it right.

I really just don't understand why your interactions with me are going in this direction. You said early in the thread that you've tried to understand what bells theorem is about. I made a post explaining what bells theorem is about. Then, somehow you went from not knowing what bells theorem is about to being incredibly confident that it's not about what I said, and you're confident bell himself would probably disagree.

But that's okay, you can disagree with me, I'm not throwing a temper tantrum about it, I'm communicating why I think what I think and defending my understanding. I'm not being aggressive towards you. I'm just trying to talk. If you don't want to talk about it you don't have to, but your role in this conversation has been quite strange and confusing from my perspective. I can't get a read on you at all. There's an air of hostility and I have no idea where it came from. And I can't understand why you're now saying you never said I misunderstood bells theorem. I'm so confused

I'm just trying to chat about this topic that I've spent a lot of energy over the past years understanding, because you said you didn't understand.

Reply to T Clark I actually have the words from Bell himself, this is the opening paragraph of his very own paper on his very own theorem (I'm having trouble getting a link on mobile, but it's easy enough to Google, just search BELLS THEOREM PAPER)

THE paradox of Einstein, Podolsky and Rosen [1] was advanced as an argument that quantum mechanics
could not be a complete theory but should be supplemented by additional variables. These additional vari-
ables were to restore to the theory causality and locality [2]. In this note that idea will be formulated
mathematically and shown to be incompatible with the statistical predictions of quantum mechanics. It is
the requirement of locality, or more precisely that the result of a measurement on one system be unaffected
by operations on a distant system with which it has interacted in the past, that creates the essential dif-
ficulty .

I believe the picture painted here by Bell himself is remarkably similar to the picture I painted of bells theorem. I painted a picture of bells theorem being about settling the difference between QM and the EPR paper, and that first statement by Bell is that this paper is going to be about that disagreement. I keep saying that it's about certain predictions of QM being incompatible with classical mechanics, and though he doesn't use the word "classical mechanics" here, he uses instead the phrase "causality and locality" - and I think it ought to be clear the relationship between that phrase and "classical mechanics" - and then says in the next sentence that that's incompatible with the predictions of quantum mechanics.

I do think that my interpretation of bells theorem is very much something Bell himself would agree with. I think I'm only barely using slightly different wording. I think I've pretty much got it. (In fact, I would argue my wording is less extreme than Bells)

The scientific side of all the Bell stuff comes in 2 parts. Part 1 is bells paper, where he argues that QM and "locality and causality" (which I'm calling classical mechanics) give irreconcilably different predictions, and then part 2 is the actual physical experiments done to confirm which of the two predictions bears out in reality, for which the nobel prize in physics in 2022 was awarded, which confirmed that we see the predictions of QM bear out.

I started my participation in this thread because I thought I could shed some light on a topic you said you didn't understand but wanted to. If you still want to, I think I've got plenty of good evidence that the understanding I have on offer is at least in the right direction. I won't quote you again though if you're done now, I just felt the need to defend my understanding given what you said about it.

Reply to tim wood

I'm going to take a minute to just ramble and muse, if that's okay. I've given an explanation of what I think Bells Theorem is about, and in a nutshell it's simply that the universe doesn't work on classical causality.

I want to clarify something - that doesn't mean it doesn't operate on causality. I believe the universe DOES in fact operate on causality, just not classical causality.

I believe that bells theorem proves that you can't say "the particle was at this specific location at time t=50", and other such classical statements about the particle at moments when it's not being measured, BUT that doesn't mean I don't think you can say anything about the particle at t=50. I think you CAN say things, objectively true things, about the particle at t=50, just not most classical things.

I said above in my response to t.clark that my wording of the implication of bells theorem is actually less extreme than bells, because bell says QM is incompatible with local casualty - I'm only saying it's incompatible with Classical local causality.

None of what I'm saying should be taken to mean things cannot be casual, or things happen for no reason. They simply mean things aren't Classically casual, and they don't happen for Classical reasons.

I have been steering clear of a specific QM interpretation, because I didn't think it would help clarify anything, but I'm starting to think that both you and t.clark might benefit from me telling you unambiguously what I think in that regard, so here it is:

I believe Many Worlds is in fact the most likely reality. Many worlds is casual (locally, I think, though some people argue it's not local) - but it is not CLASSICALLY casual. In many worlds, things happen for "reasons", deterministically, just not CLASSICAL reasons. In many worlds, you can say things about a particle at t=50, you just can't say CLASSICAL things about that particle.

The sorts of things you can say about a particle at t=50 aren't "it was at this specific location going at this velocity", instead you can say things somewhat like "the wave function of the particles position at t=50 looks a bit like this, a cloud with dense regions here and here and less dense regions here, here, here and here." These are the sorts of objective statements you can make in a quantum world about unmeasured objects. This is what I meant when I said you have to bend your mind to accept different answers to the ones you're used to expecting. Most people expect the particle to have a specific location, and not to have an amplitude distribution.

I think many worlds is the most likely reality, but I'm not super confident of it. If it's not many worlds, the most likely alternative I think is that qm operates on some level of genuine randomness with non local causality, but I think that's pretty unlikely.

I hope that sheds some light on what you're trying to touch on with your "no reason" questions, Tim - I don't believe quantum things happen for "no reason", and I don't believe the things I've said necessarily imply that.

But at the end of the day, my goal here was not to talk much about what I believe about qm, but just about what Bells Theorem is fundamentally about. I think it's just about proving that QMs predictions are incompatible with classical physics. I believe the experiments that won the Nobel prize in 2022 demonstrate sufficiently that the physics of our universe at the scale of protons and photons etc are not classical.

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Quoting tim wood

It seems to on any macro-scale.

Yes, and the standard idea there is that macro level classical behaviours are emergent from micro level quantum behaviours

Quoting tim wood

I would appreciate an excellent sentence or two on just what many-worlds is and entails. I understand it as a theory that says when you have to decide between apple and blueberry pie, the universe instantly divides into four separate and distinct universes where in each respectively you have either one or the other or both or neither. And this bifurcation occurring for every thing at every moment. But this is nonsense. How does it really work?

First of all let me say that I don't want to derail this thread about Bells Theorem to be about many worlds. I'll try to briefly answer your questions, but it's not my intention to convince you of many worlds or defend it in any way. That being said...

At the center of many worlds is not humans, so centering the discussion on human decisions is not really advisable. Imo the idea that many worlds means anything you can imagine doing, there's some world where you do it is a misunderstanding. There may be some actual proponents of many worlds who agree, but I do not.

Many worlds is about the behaviour of fundamental particles. The wave functions in QM give a probability distribution of what properties those particles have and where they might be. The "world splitting" happens in the context of that probability distribution. If a particle has 50% of being here and 50% of being there, well there are worlds where it's here and worlds where it's there.

If you imagine some scenario about pie, there's not necessarily any sequence of quantum probabilities where you choose pumpkin pie, regardless of your ability to imagine yourself doing that.

If you ask other people who prefer many worlds, they may disagree with me on that point. I'm just speaking for myself here.

Quoting tim wood

May we also agree that the reason is in some sense real? Not the description of it, although that real in an irrelevant sense. Perhaps usually the reason is some force? But whatever, real? My point here, that you may have already adverted to, being that everything that is, is real and distinct at some level in some way. (And thus that a god might know it if s/he cared to look, a perfect God always already knowing it.)

The wording here is too vague for my liking. God might know what if God cared to look?

Quoting tim wood

The wave functions themselves a function of inadequate knowledge

Not in my opinion, no. Happy to explain why if you care.

Quoting tim wood

What leads me to this is the notion of the electron as a cloud. I buy that as a description, but if it really is a cloud, then, to my knowledge, no one has yet given an account for how the cloud works.

People have given an account of that. It's called the Schrödinger equation and it's a fundamentally important equation to quantum physics. It governs how that cloud evolves over time.

Interestingly, even though the common interpretation of quantum mechanics (not many worlds) is indeterministic, this particular equation is itself deterministic. Which means that, in the common understanding, you have a deterministic function determining the probabilities, which are then selected from indeterministically.

Quoting T Clark

In my understanding, this is not true. It is your interpretation, not mine and probably not Bell's. The inequalities are not "there to help us," they describe phenomena at very small scales.

What we have here is a failure to communicate.

Quoting T Clark

In my understanding, this is not true. It is your interpretation, not mine and probably not Bell's. The inequalities are not "there to help us," they describe phenomena at very small scales.

This statement doesn't challenge Bell's theorem, it's implications, or your interpretation. It's my pedantic way of saying that science describes how the world works. It doesn't have any purpose, it's just a description.

Reply to T Clark Scientific papers are absolutely published for purposes.

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Reply to tim wood you're of course free to think many worlds is wrong headed, I'm not here to defend many worlds, I'm not qualified to defend many worlds. I was just trying to answer your questions in good faith, to humour your curiosity. Reject it as you like.

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Reply to tim wood you're still talking about "decisions", which sounds to me like human decisions. I've indicated that in my view, quantum mechanics is not about human decisions. I don't believe that every imaginable human decision is realized in some world.

Reply to T Clark my previous reply was possibly too short. I meant it as a serious reply but I'm concerned the brevity of it might come across as snark rather than serious, so let me go into detail.

Many scientific papers are published for purposes. I believe this particular paper (on the EPR paradox by John bell) was, like many, published in order to persuade people about an idea that author had. That's certainly the effect it had - it has persuaded many people of an idea.

Do you think it was published to persuade? If so, what do you think it was trying to persuade people of?

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Reply to tim wood quantum mechanics certainly RESULTS in human decisions, I'm not disputing that. I'm saying it isn't ABOUT human decisions. Quantum mechanics is mathematical equations, and there's no operator in those equations for a "human decision".

So human decisions result from quantum events, yes, but quantum events aren't generally about human decisions. Some quantum events, according to MWI, CAN occasional spawn branches of the universal wave function where one human decision happened in this branch and another human decision happened in that branch - that can happen, but it is not required to happen for every imaginable decision you think you might be able to take, in my opinion.

I don't speak for everyone who prefers MWI, though.

There's interpretations within interpretations. Agggh

Quoting flannel jesus

Many scientific papers are published for purposes.

I don't think there's much of a disagreement between you and me and what there is is metaphysical, epistemological, not scientific. You and I just seem to have trouble linking up. Let's leave it at that and I'll try harder in our next conversation.

Reply to T Clark sure, despite the misunderstanding I appreciate your participation and hope I run into you again in the future. Wish I could have expressed myself more clearly. Have a good one

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Quoting tim wood

https://static.scientificamerican.com/sciam/assets/media/pdf/197911_0158.pdf

I thought this was a really good article. I understand the subject now way more than I did, though I'm still trying to sort through it and the ramifications in my head. How did you find it, I guess you had a physical copy lying around?

To give an idea of the caliber of writer SA used to employ:
https://en.wikipedia.org/wiki/Bernard_d%27Espagnat


FWIW (probably nothing), my take on "quantum ontology" is that there is a kind of tolerancing to the universe. The universe is as exactly as specified as it needs to be, and no more. If something (a quantum state) may remain unspecified, it remains unspecified, and the range of possible states and their likelihoods exactly describe it. It is a bit analogous to "lazy evaluation" in software programming. I find this elegant and efficient, not spooky.

Reply to tim wood I don't know what any of that means, I'm sorry

Reply to flannel jesus

I've appreciated your comments here, thanks for that. Frankly I feel like he is flailing without knowing what he is talking about.

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Quoting tim wood

It seems to on any macro-scale. The "seems to" not just a throwaway phrase, but rather a pretty good clue as to what is, er, seems to be, the case. The real trick here is to not use the "I don't knows" as grounds for knowing.

What seems to be, often is not what is the case. The issue is the nature of what has been called "persistence" in this thread. And although we take persistence for granted, as indicated by Newton's first law of motion, it is demonstrably not a necessity, not necessary. That things will continue to be, as they have been in the past, is not a necessity. This is what Hume pointed to with his discussion of causation and the problem of induction, the necessity required for solid, sound conclusion of certainty, just is not there. Even Newton stated that his first law of motion was dependent on the will of God. He noticed that what this law takes for granted, that a body will continue to move, as time passes, with the same motion that it had in the past, unless caused to change, is not a statement of necessity. It is an inductive conclusion, and such conclusions lack necessity, as Hume argued.

So there is another way to look at the persistence of objects, a way which does not take for granted the continuity of existence, the persistence, which is expressed by Newton's first law. When we do not take this law for granted, then we see that what is expressed by this law requires a cause. So for example, if a body is going to continue to move in a predictable, uniform way, then at each moment as time passes, there must be a cause which makes it be at that particular predictable place. From this perspective, we do not take for granted that the body will move in a predictable way, as described by Newton's law, we understand that there must be a cause of it moving in that predictable way, and so this cause is acting on the body at each moment of passing time, making it exist at the place where the prediction dictates.

Quoting tim wood

And you know this how?

I know this by inductive reasoning. Every real physical body, object, or thing, has a location. If it does not have a location it is a fictional thing. If you are not inclined to believe that inductive reasoning can give sound premises, and you recognize that it is lacking in necessity, then you are in a good position to understand what I wrote above.

Quoting tim wood

My private opinion is that the electron is particle-like, and only cloudlike in the sense that it moves around really, really fast. And it would not offend my scientific sensibilities if someone were to suggest that maybe the particle-like in its motion sets up a kind of standing shock wave, though in what medium or made of what I don't know.

Why then does electrical energy travel through the field around copper wires, instead of traveling through the copper wires, where the electron particles are supposedly located? Or do you think that particles of the wire, the electrons are actually outside the wire?

[quote=http://scienceline.ucsb.edu/getkey.php?key=3199]However, electrical energy does not travel though the wire as sound travels through air but instead always travels in the space outside of the wires. This is because electric energy is composed of electric and magnetic fields which are created by the moving electrons, but which exist in the space surrounding the wires.[/quote]

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Reply to tim wood you brought the tone of the conversation too low with that "shameful" bit. You gotta grow up a little bit man. You shouldn't get so worked up about qm, it's not that big of a deal that someone likes one interpretation or another. Please relax about it.

I'm happy to humour your curiosity about many worlds, but not if I'm just being insulted. I don't believe I insulted you.

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Reply to tim wood The use of many worlds is arguably the same use as quantum mechanics. It's a natural interpretation of quantum mechanics given the mathematics. In fact quantum computing was partly developed by a guy who had the idea to do it because he wanted to prove many worlds. So if you think quantum mechanics is useful, and especially if you think quantum computers have the potential to become useful, you have a framework for understanding why many worlds might be part of something useful.

"Instantaneous creation of worlds", I think creation is the wrong word there. This is one of those points where there's interpretations within interpretations. Are worlds created, do they already exist, are they just splitting? I'm not into the "created" phrasing, but I guess for a casual conversation it's close enough.

Yes, worlds are splitting or getting created or however is the proper way to word it (decoherence is the central concept here), due to quantum events, constantly. But again, that doesn't necessarily mean every choice you can imagine is realized in some world somewhere. I don't think so, anyway. There are cases where worlds are split at the joint of human choices, but I think those are the exception rather than the rule.

If you want a canonical answer on that, I'm not the guy to provide that. This is just my opinion.

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You're certainly allowed to think many worlds is nonsense. Many experts in QM agree with you.

And many experts in QM also disagree. Many worlds is, as far as I can tell, the second most popular interpretation among experts. I think you'd find the first most popular also disagreeable, though, so...

John Bell himself, after which this thread is named, interestingly thinks simultaneously that Many Worlds is absurd and simultaneously a promising approach to qm. He respects it and thinks it's nonsense at the same time (or did, anyway)

I have no means of convincing you, or interest in doing so. All I can do is chat a bit about it. I think it's interesting.

Quoting Metaphysician Undercover

Why then does electrical energy travel through the field around copper wires, instead of traveling through the copper wires, where the electron particles are supposedly located? Or do you think that particles of the wire, the electrons are actually outside the wire?

However, electrical energy does not travel though the wire as sound travels through air but instead always travels in the space outside of the wires. This is because electric energy is composed of electric and magnetic fields which are created by the moving electrons, but which exist in the space surrounding the wires.
— http://scienceline.ucsb.edu/getkey.php?key=3199

I'm afraid your source is not very good. It seems to be mistaking the skin effect which is applicable to AC signals, for a general rule about electrical conduction.

In either the AC or DC case, electrical current travels through the conductor. That link provides some explanation as to why in the AC case the conduction of current becomes more and more confined to the outermost portions of the conductor as the frequency of the AC signal increases.

Quoting hypericin

To give an idea of the caliber of writer SA used to employ:

I subscribed back in the 1970s. I finally gave up because so many of the articles were over my head. I didn't take another look until the 2000s. Might as well read "Discover."

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Quoting tim wood

And TPF being the kind of site that it is, I am asking you what you think. Does MW make sense to you as a real thing?

Yeah. I'm not religious about it. I'm not certain of it, I don't think people are going to hell for disagreeing with it, I don't think only stupid people reject it. I just think it's the most compelling option.

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Many worlds is worth my favour because it provides the clearest account of what happens across the variety of quantum experiments, without resorting to too many unsavoury assumptions.

You might think a multiplicity of worlds is an unsavoury assumption already, but the alternatives are arguably, and in my estimation, even worse.

The major alternative is Copenhagen, which has the following features:

* genuine randomness
* non local casualty
* an additional arbitrary postulate on top of non local causality to explain why you can't use that non local causality to communicate faster than light

The first of the above isn't that bad, but the other two are pretty undesirable in a physical theory.

Another alternative to MWI involves accepting retro causality, which I don't like.

Basically, every alternative to MWI involves accepting stuff that is even harder to stomach than invisible alternate worlds. And believe it or not, MWI is actually *simpler* than the alternatives. So it deserves a couple points from Occam's razor

Reply to flannel jesus
To me MW is only palatable if the "worlds" are virtual, not actual. The universe consists of a finite set of resolved state and an infinite, virtual, unresolved state: the set of everything that is consistent with what is resolved. There are infinite possible worlds which are consistent with what is actual.

So for instance, an electron cloud represents all the probabilities of locations an electron may be that is consistent with the position of the nucleus (itself a tighter cloud), and the surrounding fields. These can be thought of as virtual versions of the world, and none is more actual than any other, just more or less likely. The infinite worlds collapse to a definite state of affairs when interaction with other definite states of affairs make it necessary. But this then is just the basis for a new set of virtual possible worlds.

So in the Bell experiments the two particles don't have a definite spin, the actual, resolved world is consistent with an infinite number of potential spins they may have. When they encounter a magnetic field, these virtual worlds collapse to an actual one where one has one definite spin, and the other the opposite. Since there is no consistent world where the particles have anything but opposite spins, the collapse creates the appearance of action at a distance.

This combines the genuine randomness of Copenhagen with the "out" for non-local causality of MW, without the egregiousness of gigatons of matter being created every nanosecond, at every point in space (I don't know if anyone actually believes that last bit).

Is this kind of interpretation a "thing", or am I talking out of my ass?

Quoting hypericin

So in the Bell experiments the two particles don't have a definite spin, the actual, resolved world is consistent with an infinite number of potential spins they may have. When they encounter a magnetic field, these virtual worlds collapse to an actual one where one has one definite spin, and the other the opposite. Since there is no consistent world where the particles have anything but opposite spins, the collapse creates the appearance of action at a distance.

This combines the genuine randomness of Copenhagen with the "out" for non-local causality of MW, without the egregiousness of gigatons of matter being created every nanosecond, at every point in space (I don't know if anyone actually believes that last bit).

Is this kind of interpretation a "thing", or am I talking out of my ass?

It's an interesting idea, but on the surface I'm not actually sure how it functionally is different from Copenhagen. At the moment one particle gets measured, by exactly what mechanism does the other particle know to come out measured the opposite? If it happens immediately, it's spooky action at a distance. If it doesn't happen immediately, then what does the narrative look like?

Quoting flannel jesus

At the moment one particle gets measured, by exactly what mechanism does the other particle know to come out measured the opposite?

When particles s,t are emitted, there are infinite virtual worlds where s,t can have any allowable spin. But crucially, these are the same virtual worlds, since their spins are linked. Upon measurement of s to have spin +A along one axis, the virtual worlds collapse to an actual state of affairs, where s has +A, and t has -A. The particles don't "know" anything, their spin just belonged to the same set of virtual worlds.

Quoting hypericin

the virtual worlds collapse to an actual state of affai

collapse *immediately*?

Reply to flannel jesus
I think so, yes.

Reply to hypericin I'm no expert, take this with a grain of salt, but I do believe you've described Copenhagen to a t. Including the virtualized worlds concept (it may not be standard to call it that in Copenhagen, but I believe the idea is basically that).

Or, perhaps it's a flavour of Copenhagen. Basically, it has a lot in common with Copenhagen, from my point of view.

Reply to flannel jesus
Cool, I don't know either if this meaningfully diverges from Copenhagen or not.

Reply to flannel jesus If it is Copenhagen, does this slant make it any more agreeable to you?

Reply to hypericin if the community of physicists is anything to go by, Copenhagen-type interpretations are certainly valid and worth consideration. I definitely consider them a genuine possibility.

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Quoting tim wood

it seems to me the last part is what is meant by "entanglement."

:up:

Quoting tim wood

As to randomness, I'll add this: that randomness is really hard to define. I suspect that at the level of the things themselves, nothing is merely random, for reasons I think obvious (yes?).

I'm not sure. Intuitively it might seem so, but this is a domain that is far far away from that where our intuitions were formed. God may or may not ultimately play dice with the universe, how can we say?

Quoting hypericin

I'm not sure. Intuitively it might seem so, but this is a domain that is far far away from that where our intuitions were formed. God may or may not ultimately play dice with the universe, how can we say?

Suppose instead of God we have Ged. Ged is a postdoc in a ten dimensional universe who is researching the possibility of intelligence evolving in a three dimensional universe. So Ged sets up a Monte Carlo simulation of a three dimensional universe in order to explore the possibility space. Voila, here we are in the multiple worlds of Ged's simulation. :gasp:

Quoting tim wood

As to cause, one of the basic presuppositions of Newtonian science, Newton held that some things were caused and some things were due to the operation of law

What you propose here is a distinction between things which occur because they are caused, and things which occur because there is a law operating. This places "things which are occurring because there is a law operating" into a separate category from "things which are occurring because there is a cause". The problem with this proposed separation is the problem of induction which I pointed to already. As Hume demonstrated, these "laws" are inductive, and induction does not provide the necessity required for that category "things which are occurring because there is a law operating", to completely explain any activity.

In simple terms, "there is a law operating" is insufficient to account for the occurrence of things which are said to be "due to" the operation of the law, because the relationship between these two, the occurrence of things and the law, is not one of necessity. That was Hume's point, "law" is an inductive conclusion, and induction cannot ensure that every occurrence will be according to that law. This is why Newton who was trained through Church run institutions, in the traditional manner, supported his laws with "the Will of God". Because "the operation of law" on its own, is insufficient to necessitate any contingent occurrence, the Will of God is needed to underly "law" as substance. You remove "the Will of God" from your representation, but then it does not correctly portray what Newton believed. Newton believed that "the operation of law" required the Will of God. So things which "were due to the operation of law" were understood by Newton to also be due to the Will of God.

I think you need to take a good look at the nature of "contingency", "contingent events". Suppose there is an apple hanging on a tree, and then the apple falls. You'd be inclined to say that when the apple is falling, the falling is due to the operation of law. However, prior to falling, the apple was hanging. And to transition from hanging to falling requires a cause, a bird pecked it, the stem rooted, whatever. Now, you ought to be able to see that "the operation of law" is insufficient as an explanation for any contingent event because a cause is still required at the boundary, which marks the temporal beginning of any event which occurs according to the operation of law.

So we might take a bigger event with a much longer temporal duration, than the falling apple, like the orbiting of the earth around the sun. You'd say that activity is due to the operation of law. However, just like the falling apple, this event is not eternal, it must have a temporal beginning, a cause. That every event such as this requires a cause for its existence, and cannot be explained simply as "due to the operation of law", is the reason why we call them "contingent". Even if the event is according to, or consistent with, a law, it still requires a cause, and at this point necessity was lacking, hence it is contingent. The same principle holds for quantum events of extremely short duration. Any occurrence is contingent, and requires a cause, it cannot simply be said to be due to the operation of law. This implies a very large number of causes in a very short period of time, to account for the reality of all these contingent events.

Quoting tim wood

But you it seems would take a bit of snake, and of newt and frog and bat and dog, and some other ingredients, and boil up a potion that you would call knowledge, but in fact is nonsense or worse. So, for any of your "conclusions" in your posts, never mind all your qualifications and variant perspectives, how do you know?

I have no idea what you are talking about here. I didn't talk about snakes, newts, or frogs, that's all in your imagination. And so is your assessment that what I said is "nonsense or worse". Furthermore, your question here is incoherent, you ask me to tell you how I know, without reference to my qualifications.

Quoting wonderer1

I'm afraid your source is not very good. It seems to be mistaking the skin effect which is applicable to AC signals, for a general rule about electrical conduction.

In either the AC or DC case, electrical current travels through the conductor. That link provides some explanation as to why in the AC case the conduction of current becomes more and more confined to the outermost portions of the conductor as the frequency of the AC signal increases.

Your assertion is not very convincing wonderer1. I've read a fair bit of material authored by Richard Feynman, much is available on the net. And, he is very explicit in saying that the flow of current is not in the body of the conducting material, because the electrons are freed from the atoms, and the flow is therefore in the field.

Quoting Metaphysician Undercover

Your assertion is not very convincing wonderer1. I've read a fair bit of material authored by Richard Feynman, much is available on the net. And, he is very explicit in saying that the flow of current is not in the body of the conducting material, because the electrons are freed from the atoms, and the flow is therefore in the field

It's not clear to me what you have in mind with "because the electrons are freed from the atoms". Are you imagining these free electrons as being outside the body of the conducting material, and that the movement of electrons inside the body of the conductor does not play a role in the propagation of energy through the fields?

On your view, why does it matter what material the conductor is composed of, or what the cross sectional area of the conductor is?

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Reply to hypericin

I thought it would be worth potentially elucidating why the non-local causality of Copenhagen was problematic for Einstein (why he called it spooky action at a distance) and why it remains problematic for other physicists. None of this is meant to be proof that it can't be correct, only an explanation for why it isn't taken at face value as obviously the correct interpretation.

Physicists, for what you might call "aesthetic" reasons, have I think always tended preferred local causality rather than instantaneous-across-distances causality since physics was even a thing. Einstein himself changed that from a mere aesthetic preference to something a bit more substantial.

Einstein is of course credited with Relativity, and specifically of interest to this conversation is Relativity of Simultaneity. If you observe two events, one over here and one over there, you may be able to say "this event happened before that event". Einstein's relativity of simultaneity says there is some other observer in some other reference frame who can say the opposite "that event happened before this event" - and in relativity, it's not that one of you is right and the other is wrong. You're both right, in your own reference frame.

Now, when events are happening locally, everyone agrees which one happened before the other one. This problem of disagreeing order of events only happens with events that are separated in space.

So, back to Bell's Theorem. You're at a reserch facility. At the middle, you have an apparatus that generates entangled electrons and sends one east, to you, 50m, and one west, to your research partner Alice, 50.000000001m - she's very slightly further away from the middle than you. So, you generate an entangled electron pair, you measure the spin as Up, Alice measure's the spin as Down just a tiny fraction of a second later. The causal narrative of Copenhagen says, you measured your electron as Up, then immediately, faster than light, the virtual worlds collapsed and guaranteed that Alice would measure her spin as Down.

Relativity of simultaneity says, there's some equally valid reference frame where actually, Alice measured the spin as Down first, and that's what caused the collapse of the virtual worlds, the wave function, which caused you to measure yours as Up.

When you combine Relativity with Copenhagen, you get this strange picture of causality. You can't objectively, universally say A caused B, because it's equally valid to say B caused A. THIS is what "spooky action at a distance" means. This is what's spooky about it. This is why Einstein couldn't stand QM when he first learned of it.

Again, this doesn't mean Copenhagen is incorrect, it's just meant to give you some context as to why some people aren't satisfied with Copenhagen.

Quoting wonderer1

On your view, why does it matter what material the conductor is composed of, or what the cross sectional area of the conductor is?

I made a reply to tim wood's statement of opinion "the electron is particle-like, and only cloudlike in the sense that it moves around really, really fast." On the other hand, it is my opinion that the transmission of energy through a field cannot be adequately represented as particles moving really really fast. In fact, what I've been arguing is that the representation of such energy transmission as through particles is completely wrong. This is compatible with what flannel jesus is arguing, that the outcome of Bells theorem is that the classical representation of energy as the property of bodies (particles in this case) is fundamentally inadequate.

Of course "the body" of the conductor plays a role, and that's why I argued elsewhere in the "Entangled Embodied Subjectivity" thread, that it makes no sense to talk about "just the field", as if the field could exist without the body. This specific problem, I believe is due to the deficiencies in our understanding and conceptualization of what is called "the field".

Since there is no ether identified as the medium within which the waves exist, the only substance which this concept is grounded in is the body which the field is a property of. Establishing the correct relationship between body and field is problematic in current conceptualizations. If the ether which is logically required to support the real existence of waves, was identified such that its real properties could be tested, this would allow us to conceptualize independent existence of the waves, enabling us to properly conceive of the waves as prior in time to the body, and therefore the appearance of a body (particles, atoms, molecules, etc.) as property of the waves. But this implies a conception of the waves which would be completely distinct from the current "field".

Quoting Metaphysician Undercover

Since there is no ether identified as the medium within which the waves exist, the only substance which this concept is grounded in is the body which the field is a property of. Establishing the correct relationship between body and field is problematic in current conceptualizations. If the ether which is logically required to support the real existence of waves, was identified such that its real properties could be tested, this would allow us to conceptualize independent existence of the waves, enabling us to properly conceive of the waves as prior in time to the body, and therefore the appearance of a body (particles, atoms, molecules, etc.) as property of the waves. But this implies a conception of the waves which would be completely distinct from the current "field".

You got me interested, so I googled this up:

https://physics.stackexchange.com/questions/308413/ether-vs-quantum-field-theory

Just posting it here because it's interesting. Maybe you'll find it as interesting as I did.

I do think the usual idea of the fields is that the waves aren't distinct from the field, the waves are literally perturbations of the field. I don't know if there's any conception of quantum fields where the waves are somehow distinct from the field, never heard of that idea before.

Reply to flannel jesus

Interesting. Does MW "solve" this somehow?

Reply to hypericin yes, world splitting is not a global event. World splitting in MWI actually happens at the speed of causality.

Reply to flannel jesus In that case, I hereby modify my "theory", the virtual world collapsing also happens at the speed of causality (aka light?) :P

This means that MW and Copenhagen aren't just interpretations, they are different theories, and there must be a way to test their differing predictions, right?

Reply to hypericin if it happens at the speed of causality in your interpretation, then you're left with explaining what's happening on Alice's side when she measures DOWN after Bob measured UP. Do 2 Alices exist at once, one who saw down and one who saw up?

Many worlds does, in fact, have 2 Alices, and 2 Bob's, which is why the worlds don't have to split globally immediately. But in your idea, there aren't 2 real Alices in 2 real worlds, which means you've got some tricky things to deal with.

If you believe there's only ever one real Alice and one real Bob, then the worlds CAN'T just split at the speed of causality. They have to split fast enough so that Alice's result is guaranteed to be opposite to Bobs, but the split can only begin happening as soon as Bob has measured. It takes near instantaneous casualty to make that happen.

Reply to hypericin if my above explanation isn't sufficient to make it clear why single-world Copenhagen type interpretations require faster than speed of light communication to happen, I'm happy to illustrate in much more detail.

Also, just clarifying something I said a couple posts ago - the phrase "speed of causality" means "slower than or equal to the speed of light".

Reply to flannel jesus
:chin: Lemme think about it. Feel free to elaborate if you like, you've got a real knack for it, I love your lucid explanations.

Reply to hypericin Thank you, I'll try to make it brief. It's truly just a differently-detailed example from before, but hopefully the new details are illuminating.

If you believe there is only one Alice and one Bob, then imagine a scenario like this.

You've got the entangled-photon emitter, emitting one photon East and one photon West like before. Bob is east, waiting to receive the photon 10 light seconds away. Alice is west, waiting to receive the photon 11 light seconds away.

At t=0s, the photons are emitted. At t=1, both photons are in their way to Alice and Bob respectively, BUT crucially the photons have an indeterminate spin at this moment, right? Because they haven't been measured.

At t=9, both photons are close to their respective destinations, but crucially still with indeterminate spins. Same thing at t=9.9999 right?

At t=10, Bob gets his photon and measures it as spin Up. At this moment, Alice still has not received her photon. Now, if you want this to all happen with only speed of light level causality, the problem starts to become clear:

Alice's photon is still unmeasured at t=10, and Bobs has only just been measured 20 light seconds away, which means Alice's photon must still be indeterminate, right? It was indeterminate at t=9.9999, and nothing casually exists that would have changed that in the meanwhile in our example, right?

So, here's the problem. Bob has measured Up. Bob knows for a fact Alice will measure Down. But Alice's photon is still indeterminate, and the information required to make Alice's photon collapse to "Down", at t=10, has 1 second to make it to Alice's photon. It has 1 second to travel 20-21 light seconds, to make Alice's photon spin state collapse to the matching value.

It has 1 second to travel 20-21 light seconds. The information has to travel over 20 times the speed of light to achieve this.

This is why you can't just believe in a single real world and say "my virtual worlds collapse at the speed of light".

I hope that makes sense.

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Reply to tim wood I appreciate your feedback. However, the post you're replying to is purely about why Copenhagen family of interpretations require non local casualty.

Quoting Metaphysician Undercover

Since there is no ether identified as the medium within which the waves exist, the only substance which this concept is grounded in is the body which the field is a property of. Establishing the correct relationship between body and field is problematic in current conceptualizations. If the ether which is logically required to support the real existence of waves, was identified such that its real properties could be tested, this would allow us to conceptualize independent existence of the waves, enabling us to properly conceive of the waves as prior in time to the body, and therefore the appearance of a body (particles, atoms, molecules, etc.) as property of the waves. But this implies a conception of the waves which would be completely distinct from the current "field".

I find it strange, the way you seem to get hung up on words being used in ways you disapprove of. Analogies play an important role in the way humans communicate things with each other and the use of "wave" to convey somewhat analogical things about electromagnetic fields has been going on for longer than either of us have been alive. It looks to me like you are fighting a losing battle.

What do you see as a problem, with having a notion of "wave" that needs nothing more than space to propagate through?

Quoting flannel jesus

I hope that makes sense.

Yes. I retract my amendment, my theory as originally stated stands: the virtual worlds collapse immediately.

Quoting flannel jesus

When you combine Relativity with Copenhagen, you get this strange picture of causality. You can't objectively, universally say A caused B, because it's equally valid to say B caused A. THIS is what "spooky action at a distance" means. This is what's spooky about it. This is why Einstein couldn't stand QM when he first learned of it.

I think the word "causality" is misused when applied to virtual worlds collapsing. "Causality" in the physical, actual world involves the action of forces. You can't have a situation where A can cause B, or B can cause A, depending on the frame of reference. This is illegal *not* because it bothers our intuition, but because forces are asymmetric: you can't generally get the same result if you change the sequence. The universe can't allow that, because there is only one actual world, and this would result in multiple conflicting versions of reality.

The collapse of a virtual world into actual is not caused by a force (though it can be triggered by a force). Could a force somehow push or pull a virtual world into actuality? It doesn't make sense. Rather, this operates at a deeper level, it's the underlying logic of the universe that makes causal interaction via forces possible. Unlike forces, collapses are symmetric, so it doesn't matter if A or B happens first in different frames of reference, what matters is that the outcome is the same.

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Quoting flannel jesus

I do think the usual idea of the fields is that the waves aren't distinct from the field, the waves are literally perturbations of the field. I don't know if there's any conception of quantum fields where the waves are somehow distinct from the field, never heard of that idea before.

I think what is needed here is a clear understanding of what is a "field". Wikipedia tells me that it is a geometrical representation which assigns values to various points in space. The values will
change as time passes.

What I would say, is that the changing values of the field are a representation of the real wave motion (a motion which would require an ether). However, there is no ether identified, so there is no real wave motion which can be identified. However, the field representation does show the transmission of energy through the thing represented as a field. So many physicists are inclined to just think of the field as the thing which is real, and forget about the real waves which the field represents.

Quoting wonderer1

I find it strange, the way you seem to get hung up on words being used in ways you disapprove of. Analogies play an important role in the way humans communicate things with each other and the use of "wave" to convey somewhat analogical things about electromagnetic fields has been going on for longer than either of us have been alive. It looks to me like you are fighting a losing battle.

What do you see as a problem, with having a notion of "wave" that needs nothing more than space to propagate through?

I've studied enough physics to know that a wave is an activity of a substance. That's simply what a wave is, and all waves are understood through modeling the movement of the particles within that substance. That's what a wave is, a specific type of activity of a substance which involves an interaction of its particles. Therefore a wave in empty space is simply impossible because there would be no particles there to make the wave. Yet we know from observation, rainbows, and other refractions, that light must consist of waves, therefore there must be a substance there which is waving.

Reply to hypericin are you eschewing a casual explanation altogether? If not, how does the casual narrative look?

I also want to take the opportunity again to clarify that the stuff I'm presenting is only meant to illustrate a tension between relativity and Copenhagen. It doesn't mean that Copenhagen must be incorrect, AND it may be that the tension is resolvable anyway. I'm by no means attempting to convince you to change your mind. I just think all this stuff is interesting to think about.

Quoting tim wood

The events at Alice's and Bob's detectors are not space-like separated.

Being many light seconds apart is exactly an example of what it means to be space-like separated, no? They are... separated in space.

Thank you for the kind words btw

Regarding "spin", here's a good explanation from Scientific American: https://www.scientificamerican.com/article/quantum-particles-arent-spinning-so-where-does-their-spin-come-from/

Reply to EricH Really interesting read.

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Quoting Metaphysician Undercover

Yet we know from observation, rainbows, and other refractions, that light must consist of waves, therefore there must be a substance there which is waving.

Perhaps I'm misunderstanding you, but the Michelson–Morley experiment disproved that idea.

Quoting tim wood

I invite you to listen to this:
https://www.youtube.com/watch?v=OduDEz77h9U&t=830s
You can speed it up to however fast you can listen. He makes the point that what Bell's theorem rules out is any strictly local theory (thus non-locality) At about 21:00. And that Bell's theorem in not about hidden variables(!) 24:00. The whole worth the listen

He's championing a particular interpretation, or class of interpretations here - pilot wave theory, which some argue has evolved since its invention into Bohmian mechanics. That's certainly an interpretation I have had my eye on for a long time, definitely worthy of thought and attention.

Every interpretation has its own way of answering to Bells Theorem - how a particular interpretation answers to Bells Theorem is a big part of the flavour of the interpretation itself. It's like a trade off - in order to answer to Bells Theorem, you have to choose something you want to keep in physics and choose something else you're okay with losing. Some interpretations are okay with losing "locality", for example. Some are okay with losing "realism".

That's kinda what's fascinating about qm - it took all of physicists intuitions and said, you can't keep all of them! You've got to let go of something. If you want to keep this, say goodbye to that.

Quoting flannel jesus

are you eschewing a casual explanation altogether? If not, how does the casual narrative look?

So, Alice and Bob are 11 and 10 light seconds away respectively from a dual photon emission. Charles is at the emission site, and Dave is travelling at high speed in a spaceship, away from Bob, towards Alice.

When Alice and Bob measure their spins of +A,-A, they immediately send signals telling the result. Charles measures Bob's first, and believes Bob "caused" the virtual world to become actual where Alice measures +A. Dave believes Alice received the photon first, and "caused" the virtual world to become actual, where Bob measures -A.

Both are equally correct. "Cause" is in quotes to distinguish it from ordinary cause and effect, which always involves forces. I'm speculating that this situation is OK, because unlike with forces, the resolution of virtual worlds into the actual world is invariant wrt sequence. No matter the frame of reference, the end result is the same, that Alice and Bob occupy the same actual world, and measure the opposite spin.

How this cosmic bookkeeping actually works might be beyond our ken.

Quoting flannel jesus

I'm by no means attempting to convince you to change your mind. I just think all this stuff is interesting to think about.

:100: Absolutely

Quoting hypericin

No matter the frame of reference, the end result is the same, that Alice and Bob measure the opposite spin.

The question, I guess, is what sort of mechanism allows the universe to guarantee that their measurements are opposite? That's the casual explanation I was looking for.

It's easy to guarantee opposite results if the values are pre-set as soon as the photons leave the emission site, but that's exactly what Bells Theorem seems to disallow. The mechanism for Many Worlds is called "decoherence", but that requires 2 bobs and 2 Alices. What's the mechanism in your view?

Reply to flannel jesus
:chin: :chin: :chin:
It's the right question, and a doozy... I'll have to get back to you on that one!

Reply to hypericin I thought you were going with some sort of acausal view, or at least alternative-causality view, when you were saying it doesn't matter if a causes b or b causes a. Alternative causality is something that comes up in QM sometimes.

For example, Tim Woods linked video above seems to promote the Pilot Wave family of theories, and some of those involve a sort of retro-causality - there's some "thing" that goes to the future, finds out what value needs to obtain, and then comes back in time and takes that value. Not all versions of pilot wave take that approach, but some do. I think I have some work to do to understand more about pilot wave / Bohmian ideas.

Anyway, please tag me in your next post if you have a development here.

Quoting flannel jesus

there's some "thing" that goes to the future, finds out what value needs to obtain, and then comes back in time and takes that value.

Sounds pretty unaesthetic to me. If it comes to that I might prefer MWI.

Quoting EricH

Perhaps I'm misunderstanding you, but the Michelson–Morley experiment disproved that idea.

I don't think you misunderstand me, but I do think you misunderstand what the M-M experiments disproved.

Quoting Metaphysician Undercover

Yet we know from observation, rainbows, and other refractions, that light must consist of waves, therefore there must be a substance there which is waving.

M-M explicitly disproved that notion. If there was a substance, then M-M would have detected it. That's what eventually led to relativity. If I'm misunderstanding it then please explain.

Quoting Metaphysician Undercover

I've studied enough physics to know that a wave is an activity of a substance. That's simply what a wave is, and all waves are understood through modeling the movement of the particles within that substance. That's what a wave is, a specific type of activity of a substance which involves an interaction of its particles. Therefore a wave in empty space is simply impossible because there would be no particles there to make the wave. Yet we know from observation, rainbows, and other refractions, that light must consist of waves, therefore there must be a substance there which is waving.

Ok, suppose space is the "substance there which is waving". After all, the gravitational wave observations in recent years, (combined with electromagnetic observations of the source of detected gravitational wave observations) provide some pretty good evidence for space waving.

Quoting EricH

M-M explicitly disproved that notion. If there was a substance, then M-M would have detected it. That's what eventually led to relativity. If I'm misunderstanding it then please explain.

What M-M disproved is that the relationship between massive objects, bodies, and the ether, is not as was hypothesized. That does not prove that there is no substance which is waving, it just proves that the relationship between massive objects and the substance which is waving, is not as they thought it ought to have been. I think you can read this on Wikipedia, or other online explanations of M-M.

Then, instead of trying to determine the proper relation between massive objects and the ether, the physics community decided just to dispense with the ether altogether, because that facilitated the application of Einsteinian relativity.

Quoting wonderer1

Ok, suppose space is the "substance there which is waving". After all, the gravitational wave observations (combined with electromagnetic observations of the source of detected gravitational wave observations) provide some pretty good evidence for space waving.

All right then, do you understand that a "wave" consists of an interaction of the particles which make up the substance which is the medium? So if "space" is the substance within which the waves exist, then space must be made up of particles.

Quoting wonderer1

I've studied enough physics to know that a wave is an activity of a substance. That's simply what a wave is, and all waves are understood through modeling the movement of the particles within that substance. That's what a wave is, a specific type of activity of a substance which involves an interaction of its particles. Therefore a wave in empty space is simply impossible because there would be no particles there to make the wave. Yet we know from observation, rainbows, and other refractions, that light must consist of waves, therefore there must be a substance there which is waving.
— Metaphysician Undercover

Ok, suppose space is the "substance there which is waving". After all, the gravitational wave observations in recent years, (combined with electromagnetic observations of the source of detected gravitational wave observations) provide some pretty good evidence for space waving.

Quoting Metaphysician Undercover

What M-M disproved is that the relationship between massive objects, bodies, and the ether, is not as was hypothesized. That does not prove that there is no substance which is waving, it just proves that the relationship between massive objects and the substance which is waving, is not as they thought it ought to have been.

This is completely at odds with the fundamental basis of modern physics. There's no legitimate physicist in the world who believes it. Light propagates without a medium. If you post this on a physics forum, it will be removed immediately. It's pseudoscience.

Quoting Metaphysician Undercover

All right then, do you understand that a "wave" consists of an interaction of the particles which make up the substance which is the medium?

I've already said that I have a broader perspective on using "wave" than you seem to. So no. I don't see any value in restricting the usage of "wave" to such a narrow definition.

Do you disagree that space waves in the case of gravitational waves?

Quoting Wikipedia - The Michaelson-Morley Experiment

The Michelson–Morley experiment was an attempt to measure the relative motion of the Earth and the luminiferous aether, a supposed medium permeating space that was thought to be the carrier of light waves. The experiment was performed between April and July 1887 by American physicists Albert A. Michelson and Edward W. Morley...

The experiment compared the speed of light in perpendicular directions in an attempt to detect the relative motion of matter through the luminiferous aether ("aether wind"). The result was negative, in that Michelson and Morley found no significant difference between the speed of light in the direction of movement through the presumed aether, and the speed at right angles. This result is generally considered to be the first strong evidence against some aether theories, as well as initiating a line of research that eventually led to special relativity, which rules out motion against an aether."?

Quoting Metaphysician Undercover

I think you can read this on Wikipedia,

I did and it refutes what you are saying.
Per Wikipedia:

"Physics theories of the 19th century assumed that just as surface water waves must have a supporting substance, i.e., a "medium", to move across (in this case water), and audible sound requires a medium to transmit its wave motions (such as air or water), so light must also require a medium, the "luminiferous aether", to transmit its wave motions. Because light can travel through a vacuum, it was assumed that even a vacuum must be filled with aether."

The experiment compared the speed of light in perpendicular directions in an attempt to detect the relative motion of matter through the luminiferous aether ("aether wind"). The result was negative, in that Michelson and Morley found no significant difference between the speed of light in the direction of movement through the presumed aether, and the speed at right angles. This result is generally considered to be the first strong evidenceagainst some aether theories, as well as initiating a line of research that eventually led to special relativity, which rules out motion against an aether.

These results have been repeatedly confirmed.

Reply to T Clark Ha - you beat me to it!

Quoting EricH

Ha - you beat me to it!

I don't think they're paying attention to me. Perhaps they'll listen to you.

Quoting T Clark

I don't think they're paying attention to me.

Am I among "they"?

Quoting T Clark

This is completely at odds with the fundamental basis of modern physics. There's no legitimate physicist in the world who believes it. Light propagates without a medium. If you post this on a physics forum, it will be removed immediately. It's pseudoscience.

The idea he's presenting here is that of quantum field theory if I understand him correctly - he did bring that up before. Quantum field theory is, by my understanding, far from pseudo science, though the comparison between quantum field theory and the aether *might* be - it seems like at least a fair comparison to think of, but I don't know enough to say why it's not.

I have read, though, that the fields of quantum field theory are supposed to be "relativistic", which I guess implies that they wouldn't conflict with the Michelson–Morley experiment anyway. Whether these fields could be consider an aether or not, and why not, might be an interesting question.

Or maybe you're right and it's pseudo science, but I guess I don't know enough to say it is at this point

Edit. https://physics.stackexchange.com/questions/308413/ether-vs-quantum-field-theory#:~:text=The%20quantum%20fields%20though%20by,identified%20with%20the%20luminiferous%20aether.&text=The%20aether%20or%20luminiferous%20aether,that%20which%20light%20travelled%20through.

The comparison is an understandable one to bring up, I think, but this answer illuminates what I was saying above: the quantum field(s) being Lorenz invariant makes it fundamentally different from the aether

Edit 2.

Answer here is interesting as well: https://physics.stackexchange.com/questions/518806/do-qft-fields-constitute-an-ether

Reply to EricH
Quoting T Clark

This is completely at odds with the fundamental basis of modern physics. There's no legitimate physicist in the world who believes it. Light propagates without a medium. If you post this on a physics forum, it will be removed immediately. It's pseudoscience.

It's not pseudoscience which I am engaged in, because I do not pretend to be doing science. I am speculating in metaphysics and not at all pretending to be doing physics. The larger problem though is with the way that many people regard physicists. If a physicist speculates in metaphysics, many individuals will believe that such speculations are actually science because the speculations are carried out by a scientist.

Clearly such speculations, even if carried out by a scientist, are not science. And in reality, unless the physicist is properly educated in metaphysics, this physicist is just an undisciplined metaphysician, practising pseudo-metaphysics. Steven Hawking is a prime example of a pseudo-metaphysician. He clearly had very little if any training in metaphysics, yet in books like "The Grand Design" he pretended to be well-versed in it.

Quoting Wikipedia - The Michaelson-Morley Experiment

The experiment compared the speed of light in perpendicular directions in an attempt to detect the relative motion of matter through the luminiferous aether ("aether wind").

This is the key point, the attempt to detect "relative motion" of matter through the ether. If it is the case that matter as well as the waves are both properties of the ether, then there would be no such relative motion, what we perceive as matter would just be a moving part of the ether. And, this is supported by quantum field theory. Particles of matter are understood as properties of the field, not distinct from (so as to move relative to) the field.

Quoting flannel jesus

The comparison is an understandable one to bring up, I think, but this answer illuminates what I was saying above: the quantum field(s) being Lorenz invariant makes it fundamentally different from the aether

It's fundamentally different from the aether, because the aether was always understood as an independent, separate substance from the bodies which exist within it. This was the premise of the M-M experiment. Now, respecting the results of M-M, we can either say that this was a misunderstanding of the aether, and produce a new model of the aether which does not have that requirement, or we can insist that "separate substance" is essential to the conception named "aether", and therefore dismiss "aether" as inadequate, and come up with a new word to refer to the medium for light.

Clearly, "field" is inadequate because it represents the medium with random locations, arbitrary points, instead of identifying the true particles which must exist within the medium, comprising the medium, as is required to support the observed wave motion of electromagnetism. Only through identification and modeling of the true particles of the medium can an adequate understanding of it be produced. And according to what M-M indicates (no aether wind), along with what the experiments of quantum field theory indicate, all massive objects must be composed of this same medium.

Quoting Metaphysician Undercover

I am speculating in metaphysics and not at all pretending to be doing physics.

I don't speculate in metaphysics so I can't help you with this. I suggest you take your speculations to a physics forum - they will help you understand this much better than I.

Quoting flannel jesus

The idea he's presenting here is that of quantum field theory if I understand him correctly - he did bring that up before. Quantum field theory is, by my understanding, far from pseudo science, though the comparison between quantum field theory and the aether *might* be - it seems like at least a fair comparison to think of, but I don't know enough to say why it's not.

This from Wikipedia:

Quoting Wikipedia - Quantum Field Theory

In theoretical physics, quantum field theory (QFT) is a theoretical framework that combines classical field theory, special relativity, and quantum mechanics. QFT is used in particle physics to construct physical models of subatomic particles and in condensed matter physics to construct models of quasiparticles.

QFT has nothing to do with the propagation of light. Propagation of light does not involve movement of particles within a substance. Saying that it does is wrong. It's not only merely wrong, it's really most sincerely wrong. How wrong does something have to be before it becomes pseudoscience?

Quoting Metaphysician Undercover

It's not pseudoscience which I am engaged in, because I do not pretend to be doing science. I am speculating in metaphysics and not at all pretending to be doing physics.

You wrote:

Quoting Metaphysician Undercover

I've studied enough physics to know that a wave is an activity of a substance. That's simply what a wave is, and all waves are understood through modeling the movement of the particles within that substance.

This is not a metaphysical statement. In this context it's a statement about optics, the physics of light, and it's wrong.

Quoting Metaphysician Undercover

This is the key point, the attempt to detect "relative motion" of matter through the ether. If it is the case that matter as well as the waves are both properties of the ether, then there would be no such relative motion, what we perceive as matter would just be a moving part of the ether. And, this is supported by quantum field theory. Particles of matter are understood as properties of the field, not distinct from (so as to move relative to) the field.

Again - this statement is at odds with the fundamental basis of modern physics.

Reply to T Clark quantum field theory has EVERYTHING to do with the propagation of light.

Quoting flannel jesus

quantum field theory has EVERYTHING to do with the propagation of light.

Do you believe that light must have a medium in order to propagate as a wave? It doesn't.

Reply to T Clark my beliefs aren't relevant. I'm just exploring the topic.

Even though my beliefs aren't relevant here, I'll answer the question honestly: I'm completely agnostic. I would defer to the experts. If the experts of quantum mechanics think that quantum field theory is true, then I might further ask if that field could reasonable be called an aether (even if it's not the same as the original aether concept the MM experiment tested for), and/or ask them if they would describe the field as a "medium through which light propagates".

If quantum field theory is correct, then that would mean light does in fact propagate via a quantum field. Right? That's the idea. It seems to be the idea to me, anyway.

Based on my readings, it seems the consensus is that while these fields perhaps have some conceptual overlappings with the aether theory tested in MM, a quantum field is *fundamentally different* in some important ways that make people justifiably reluctant to call it "aether".

It's not clear to me what degree of ontological "existence" these fields are taken to have by the proponents of qft, or if instead they're considered an abstract mathematical model. Is it a "thing" that occupies all of space? I really don't know.

Quoting T Clark

This is not a metaphysical statement. In this context it's a statement about optics, the physics of light, and it's wrong.

You're displaying very poor reading skills T Clark. Please reread the statement you quoted. It's not at all a statement about the physics of light. I never mentioned "light" or "electromagnetism". It's a statement about what it means to be a "wave", how the concept indicated by that word is understood through normal human conventions, especially as it is used in the more specific physics of waves.

So, if light exists as a wave, which much evidence indicates, then it exists according to the principles understood by the concept signified by "wave", which i was talking about in the statement. It is a simple conclusion of deductive logic. P1, Waves have x essential properties. P2 Light exists as waves. C Therefore light has X properties.

Quoting T Clark

Again - this statement is at odds with the fundamental basis of modern physics.

It might be "at odds with the fundamental basis of modern physics" but it's a true statement about the logical conclusion we can draw from the M-M experiments, if we adhere to the premise that light exists as a wave. As the article you quoted stated, the experiment was an attempt to detect the relative motion of matter through the aether. The experiments could not determine any such relative motion, and strongly indicate that there is no such relative motion. From here we can either conclude that there is no aether therefore light does not exist as waves, but for some unknown reason appears to be spookily similar to waves, or we can maintain the premise that light exists as a wave, therefore there is an aether: and from the results of those experiments we can conclude that matter moves with the aether, so that there is no such relative motion. If modern physicists have failed to draw the latter conclusion, and cannot understand why light spookily appears to exist as a wave, then that is a problem with modern physics, not a problem with my statement, which is at odds with modern physics.

Quoting Metaphysician Undercover

It's a statement about what it means to be a "wave", how the concept indicated by that word is understood through normal human conventions, especially as it is used in the more specific physics of waves.

So, if light exists as a wave, which much evidence indicates, then it exists according to the principles understood by the concept signified by "wave", which i was talking about in the statement. It is a simple conclusion of deductive logic. P1, Waves have x essential properties. P2 Light exists as waves. C Therefore light has X properties.

Phenomena in the world are not constrained to behave in accordance with our definitions. Before Michelson-Morley, people did believe that a medium was required for a wave to propagate. It took them a while to be convinced otherwise. Your definition is 150 years out of date.

This user has been deleted and all their posts removed.

Quoting Metaphysician Undercover

So, if light exists as a wave, which much evidence indicates

The behavior of particles at the atomic & sub-atomic levels does not correspond to anything in the macro world (AKA classical physics) - and analogies to the behavior of matter at the macro level (what we can see/fell) fall apart if taken literally.

Light does not "exist as a wave". Light "exists" (and I put exists in quotes) as photons. Photons exhibit the behavior of particles when we measure their "particle" behavior. While photons have no rest mass (since they travel at the speed of light) they have momentum which can be measured and under some situations actually used (think of outer space light sails).

Photons also exhibit properties of a wave - but only when we try to measure their wave properties (wavelength, etc).

We cannot simultaneously measure both the particle & wave behavior of photons at the same time.

So the best analogy I can come up with is that photons are particles which also exhibit wave-like behavior. And particles do not need a medium in which to move.

[edit] Just to emphasize - that is an analogy. The math describes reality.

I hope this helps.

Quoting T Clark

Phenomena in the world are not constrained to behave in accordance with our definitions. Before Michelson-Morley, people did believe that a medium was required for a wave to propagate. It took them a while to be convinced otherwise. Your definition is 150 years out of date.

This is not at all true. The physics of waves is very definite. Waves require a medium. All physicists know this, it is taught in basic high school level physics. This is why light is understood by physicists to exist as particles, photons, not as waves, and the movement of photons is understood by "wave functions", not waves Reply to EricH

Quoting EricH

So the best analogy I can come up with is that photons are particles which also exhibit wave-like behavior.

That's right, the principles of physics force us to treat this as "wave-like behaviour". This will be the case until we determine and identify the medium, at which time we will be able to treat it as true waves, which the empirical evidence indicates that it obviously is. Consider, that thousands of years ago people understood sound to be vibrations in the air. They knew, by its behaviour, wind and sound vibrations, that "air" had to be a medium, but they could not see it, nor identify the particles which air is comprised of. Having no capacity to see or identify any particles of air did not prevent them from developing an understanding of "air" as a substance. This is the same way that we should look at the aether. The evidence, wave-like behaviour, indicates that it is there, we just have not yet been able to understand its existence.

Quoting Metaphysician Undercover

This is not at all true. The physics of waves is very definite. Waves require a medium. All physicists know this, it is taught in basic high school level physics. This is why light is understood by physicists to exist as particles, photons, not as waves, and the movement of photons is understood by "wave functions", not waves

Clearly there's no reason for you and me to continue this discussion.

I do have this to say to anyone else reading this post - The fact that light can propagate as a wave through a vacuum with no medium is an established scientific fact. It's part of the foundation of modern physics. In order to reject that, you will have to reject the findings of physics for the past 150 years.

Quoting EricH

So the best analogy I can come up with is that photons are particles which also exhibit wave-like behavior. And particles do not need a medium in which to move.

:up:

Quoting T Clark

The fact that light can propagate as a wave through a vacuum with no medium is an established scientific fact

I think you've been corrected on this, the proper scientific description is "wave-like behaviour".
So, I'm going to throw your line right back at you, and please, quit with this assertion of "established scientific fact".
Quoting T Clark

It's pseudoscience.

Reply to Metaphysician Undercover

As I indicated, I'm all done.

This user has been deleted and all their posts removed.

Quoting tim wood

The concept of the aether has long since been discredited and discarded

The classical notion, yes, but perhaps not quite that simple. From Wikipedia:

Physicist Robert B. Laughlin wrote:

It is ironic that Einstein's most creative work, the general theory of relativity, should boil down to conceptualizing space as a medium when his original premise [in special relativity] was that no such medium existed [..] The word 'ether' has extremely negative connotations in theoretical physics because of its past association with opposition to relativity. This is unfortunate because, stripped of these connotations, it rather nicely captures the way most physicists actually think about the vacuum. . . . Relativity actually says nothing about the existence or nonexistence of matter pervading the universe, only that any such matter must have relativistic symmetry. [..] It turns out that such matter exists. About the time relativity was becoming accepted, studies of radioactivity began showing that the empty vacuum of space had spectroscopic structure similar to that of ordinary quantum solids and fluids. Subsequent studies with large particle accelerators have now led us to understand that space is more like a piece of window glass than ideal Newtonian emptiness. It is filled with 'stuff' that is normally transparent but can be made visible by hitting it sufficiently hard to knock out a part. The modern concept of the vacuum of space, confirmed every day by experiment, is a relativistic ether. But we do not call it this because it is not accepted (taboo).

Quoting tim wood

Starting with MIckleson-Morley in 1887, and successive experiments, it has become understood and accepted by anyone with at least a high school, or even junior high school, science class that the aether simply does not exist. And this is the science of the thing.

Well, I myself, am very sound evidence that this statement is a blatant falsity. And why do you think that this is "the science of the thing" when it's really the pseudoscience of the thing. In reality, it's just a denial of what can logically be concluded from Michelson-Morley type experiments, and denial of the current body of evidence, in a hypocritical effort to adhere to some dogmatic stipulations.

Reply to jgill

This is unfortunate because, stripped of these connotations, it rather nicely captures the way most physicists actually think about the vacuum. . . .

The denial is like a fear of God. But good theologians have progressed far beyond this attitude of instilling fear, the conventional approach now is to cultivate the love of God. Why are scientists so primitive in their behaviour, showing outright fear of the unknown, as if they will be punished if they step off the beaten path to the slaughterhouse?

Quoting tim wood

You're in a science discussion, which you are determined to derail, and your account is just that you're "doing" no science at all, but metaphysical speculation.

This happens to be a philosophy forum, not a science forum, so the participants in any discussion are more likely to be philosophers rather than scientists. So you ought to expect that your thread would contain philosophical points of view instead of insisting that we adhere to some dogma of pseudoscience.

This user has been deleted and all their posts removed.

Quoting jgill

The classical notion, yes, but perhaps not quite that simple.

You're being a bit disingenuous. The Laughlin quote you provided refers to the quantum vacuum, not the luminiferous aether. Yes, the quantum vacuum is an established fact, but it is not the medium through which light was once thought to propagate.

This user has been deleted and all their posts removed.

A science of the undetectable is a curious thing indeed. Metaphysical.

Quoting tim wood

And of course Mickleson-Morley is "pseudoscience" and "blatantly false."
10 hours ago

Tim woods, your reading skills are as bad as T. Clark's. I didn't say "Mickleson-Morley is 'pseudoscience'". I was arguing that the conclusion, that some people draw, that Michelson-Morley type experiments have proven that there is no medium for light waves, is pseudoscience.

Quoting tim wood

Typical. You're asked three questions, which you ignore. You confuse "forum" with "discussion." And of course Mickleson-Morley is "pseudoscience" and "blatantly false."

I ignored your questions because each one of them except the last requires a very long essay, and I really do not see the relevance of the material. If you want to know what "cause" and "metaphysics" mean, try looking them up. If you want to know more precisely, my use, in a specific context, then provide the context. Otherwise I'll continue to ignore such questions as unnecessary distractions. The third question I had already answered so that's why I ignored it. Here, I'll repost.

Quoting Metaphysician Undercover

It's fundamentally different from the aether, because the aether was always understood as an independent, separate substance from the bodies which exist within it. This was the premise of the M-M experiment. Now, respecting the results of M-M, we can either say that this was a misunderstanding of the aether, and produce a new model of the aether which does not have that requirement, or we can insist that "separate substance" is essential to the conception named "aether", and therefore dismiss "aether" as inadequate, and come up with a new word to refer to the medium for light.

Clearly, "field" is inadequate because it represents the medium with random locations, arbitrary points, instead of identifying the true particles which must exist within the medium, comprising the medium, as is required to support the observed wave motion of electromagnetism. Only through identification and modeling of the true particles of the medium can an adequate understanding of it be produced. And according to what M-M indicates (no aether wind), along with what the experiments of quantum field theory indicate, all massive objects must be composed of this same medium.

If that doesn't answer your third question, let me know what is lacking.

Quoting tim wood

The idea is that MU can have his aether - there is no evidence for it - as what he calls metaphysical speculation, and which I disqualify of substance in a scientific discussion.

Have fun with your so-called "scientific discussion". I'll leave you to your pseudoscience now.

Quoting Metaphysician Undercover

I was arguing that the conclusion, that some people draw, that Michelson-Morley type experiments have proven that there is no medium for light waves, is pseudoscience.

So just to be clear, you sincerely believe that Einstein (along with the entire scientific community) misinterpreted the results of M-M and are engaging in some form of pseudoscience?

Reply to EricH It's not obvious to me that he's disagreeing with Einstein at all. Einstein at times seems to provide quotes suggesting he himself believes in an aether of sorts - just one that's Lorentz invariant, which makes it compatible with relativity.

Here's a quote from Einstein himself:

• According to the general theory of relativity space without ether is unthinkable

Quoting EricH

So just to be clear, you sincerely believe that Einstein (along with the entire scientific community) misinterpreted the results of M-M and are engaging in some form of pseudoscience?

No, I believe that there is divided opinion in the "scientific community", and many members of it do not even form an opinion about this, because it is not necessary for their purposes. Most physics is applied physics, and the extremely speculative part is better known as metaphysics. The majority of scientists do not venture into this, "metaphysics", or make their opinions (if they have them) known. So I believe members of this forum are making unjustified generalizations (inductive conclusions) with statements like "along with the entire scientific community".

Here's something to consider Eric. Relativity theory was created for pragmatic purposes, and is fundamentally not truth-apt. Relativity gives us very useful principles for application, and modeling motions, but it cannot give us truth. When Galileo first developed modern relativity, he used it to show that both the geocentric, and heliocentric models of the motions of the sun and planets are compatible and equally valid, by the precepts of "relativity". However, most of us believe that there is a "truth" to the modeling of the solar system, and we know that to get to the truth of this matter, we need to go beyond what "relativity" provides for us.

Since relativity models movement as relative to an artificial frame of reference, rather than as relative to a background "space", the reality of the background is ignored. Simply put, since we do not know the reality of the background, we replace it with known frame of reference, which serves the purpose. The frame of reference is designed for the purpose, it is not designed to truthfully represent a "real" background.

This became a problem for relativity theory because things like light, and gravity, were considered as properties of the background. It made classical relativity theory inconsistent with the observed movement light. So Einstein proposed that if we make some stipulations about the speed of light relative to moving bodies, and the passage of time, we could establish compatibility between the movement of light, and the movement of bodies, and bring light and gravity to be consistent with relativity theory. This opened up a whole new field of usefulness for relativity theory, Einsteinian relativity.

The fundamental issue remains though, relativity theory is pragmatically oriented, and is designed to ignore the importance of truth. This is why we have physicists like Stephen Hawking proposing ontologies such as "model-dependent reality", and others with the idea that the universe is a "simulation". If we ignore this fundamental fact, that relativity is designed to be useful, but with its usefulness we sacrifice the possibility for truth, and instead we start to think that relativity theory is true, this induces the possibility of all sorts of strange ontologies to support the "reality" of relativity.

Now we have a backward approach to metaphysics. Instead of basing our metaphysics in strong principles directed toward truth, we direct or metaphysics away from truth to support relativity theory which denies the possibility of truth. So, as metaphysicians looking for truth, the proper approach is to observe and understand all features of reality, and build a consistent ontology accordingly. This means the influence of useful theories like relativity must not be given undue preference, because the goal is truth, which relativity is not directed toward.

Quoting Metaphysician Undercover

Relativity theory was created for pragmatic purposes, and is fundamentally not truth-apt.

Black holes, gravitational lensing, and gravitational waves have all been observed and were predicted on GR. What do you mean by relativity theory not being truth-apt?

Reply to wonderer1 I have the same question. "Not truth apt" is an interesting phrase. It's like he's not saying it's false or wrong, it's like he's saying it's not even in the category of things that can be right or wrong. Now, I certainly accept that there are things that could be described like that, but I can't see that relativity is in that group.

Quoting flannel jesus

According to the general theory of relativity space without ether is unthinkable

I used your quote to track down the article - "Ether and the Theory of Relativity" by Albert Einstein. Here's a link:

https://mathshistory.st-andrews.ac.uk/Extras/Einstein_ether/

Really great paper taken from a lecture in 1920. I've been looking for something like this for a long time.

Your quote is taken quite a bit out of context. It is clear the "ether" Einstein is talking about is space or space-time, not a luminous ether which is the supposed medium for the propagation of light. He makes that distinction explicitly.

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Quoting tim wood

Since effing when has science ever been "truth-apt"? Where in any edition of the scientific method does "truth" enter in. And another question to you, what is it that you imagine "truth" to be?

OK, so now we see a big difference between science and metaphysics. I would say metaphysics seeks truth, and truth means corresponding with reality. This would answer Reply to wonderer1''s question as well.

Prediction in itself is a usefulness, but usefulness is limited by the intended purpose, so prediction does not necessarily indicate truth. A person can successfully predict that the sun will rise the next day, using nothing but statistics. With even more information the person can predict the time and place that the sun will rise. All these predictions are based in assumptions of continuity, that things will continue to occur in the way that they have in the past. But these predictions, and the ability to predict, give no indication of an understanding of what is actually going on. This is obviously the case with quantum mechanics, and quantum field theory right now, there is a tremendous ability to predict, without any understanding of what is actually going on.

"Truth" implies an understanding of what is going on, which takes us beyond the ability to predict. What Galileo showed with relativity theory, is that an understanding of what is going on is not a requirement for the capacity to predict the notions of bodies. All that is required is an adequately formulated frame of reference, information from the past, and the fact that the bodies will continue to move as they have (as Newton's first law). So the motions of bodies can be equally predicted from distinct frames of reference, as Galileo showed with the geocentric and heliocentric models, and what is really going on (the truth) is completely irrelevant to the capacity to prediction.

This is why we have scientists like Stephen Hawking promoting ontologies like "model-dependent realism", within which the fundamental principle (or presupposition) is that there is no such thing as what is really going on. This is because pragmatic theories, such as relativity, dismiss "what is really going on" as unnecessary for making predictions. Then scientists turn to prediction as the sole purpose of science, neglecting a key part of the scientific process, which states that the usefulness of prediction is to be directed at verifying theories, and this clearly indicates that prediction ought not be the end in itself.

When prediction is not taken to be the end in itself, we clearly see the limitations to relativity theory, where it cannot accurately predict.

Quoting tim wood

Metaphysics has been defined as either the study of being, which is the study of nothing at all, because if being has any predicates it ceases to be just being.

Boy your logic skills are pathetic.

Quoting tim wood

Cause is so difficult a concept to make rigorous that for a century most of science has dispensed with its use as a meaningful term, except in informal usage where it stands as a shorthand, or in the few areas it may still be used.

Ok. now you admit it. Cause does not have a scientific definition. Why did you keep asking me for a scientific definition of cause, then ridicule me when I did not provide it? And if I would have provided you with a definition of "metaphysics", you would have made fun of it as well, based on what you now admit as your prejudice.

Your questioning is nothing but deception, trickery. The questions are intentional designed for one purpose only, and that is to trick someone into saying something which you can poke fun at. Your mode of discussion is simply disgusting.

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Quoting Metaphysician Undercover

I would say metaphysics seeks truth, and truth means corresponding with reality.

We're going way off topic here, but when you use the word "truth" are referring to the Correspondence Theory of Truth?

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Reply to tim wood AFAICT we're basically in agreement here.

[edit] But I'm curious what MU has to say.

Quoting EricH

We're going way off topic here, but when you use the word "truth" are referring to the Correspondence Theory of Truth?

Yes, that's what I said, truth means corresponding with reality, therefore I'm using "truth" in the sense of correspondence theory.

Quoting Metaphysician Undercover

Yes, that's what I said, truth means corresponding with reality, therefore I'm using "truth" in the sense of correspondence theory.

I'm still not clear on your usage of the word truth - because I went back and am seeing this:
Quoting Metaphysician Undercover

"Truth" implies an understanding of what is going on, which takes us beyond the ability to predict.

E.g., if I say that I observed an object in a vacuum chamber accelerating towards the center of the earth at 9.8 m/sec**2, I think you would agree that that is a true statement (it corresponds with reality). But there is no understanding in that statement - it's just an observation.

Also, is there a distinction when you put the word in quotes?

Quoting EricH

E.g., if I say that I observed an object in a vacuum chamber accelerating towards the center of the earth at 9.8 m/sec**2, I think you would agree that that is a true statement (it corresponds with reality).

No I don't agree with that at all, far from it in fact. Why would I just take it for granted that this is a true statement? I would have to see your justification, your measurement technique, and how you come up with "sec**2". What does "sec**2" even mean?

Furthermore, I disagree that this is "just an observation", it is actually a very complex calculation. That something is "accelerating" requires a multitude of measurements of velocity, and each measurement of velocity requires multiple determinations of spatial-temporal location.

.Quoting EricH

Also, is there a distinction when you put the word in quotes?

I put the word in quotes, because I was talking about the meaning of that word, which I put in quotes.

Quoting Metaphysician Undercover

What does "sec**2" even mean?

https://www.quora.com/What-does-per-second-squared-mean

Quoting Metaphysician Undercover

That something is "accelerating" requires a multitude of measurements of velocity, and each measurement of velocity requires multiple determinations of spatial-temporal location.

Assume all of that is done to your satisfaction beyond all reasonable doubt.

" **2 " means raised to the second power (i.e. squared). So " **3 " means raised to the third power, etc. This is standard scientific notation.

N.B. - I believe there is a way to do superscripts in the forum interface but I don't know how to do that.

Quoting EricH

Assume all of that is done to your satisfaction beyond all reasonable doubt.

The concept of "acceleration" involves a fundamental philosophical problem. Acceleration is the rate of increase of velocity. So if an object goes from being at rest, to moving, there is a brief period of time where its "acceleration" is necessarily infinite. This is a fundamental measurement problem, and another form of the same problem is at the heart of the uncertainty principle of quantum physics, as the uncertainty relation between time and energy in the Fourier transform.

This problem was exposed by Aristotle as the incompatibility between the concept of "being" (static) and the concept of "becoming" (active). The way that modern physics deals with this problem, through the application of calculus does not resolve the problem. It simply veils the problem by allowing the unintelligible issue, infinity, to be present within the mathematical representation.

Now, the very same philosophical problem which Newton and his contemporaries had to deal with in the relationship between bodies, becomes paramount in modern physics in its relationships of energy. The issue though, is that Newton and his contemporaries were dealing with relatively long durations of time, so the methods of calculus were adequate for covering up this problem which only increases as the period of time is shortened. Now physicists are dealing with extremely short durations of time, so the uncertainty becomes very relevant and significant. That's what the time/energy uncertainty indicates, the shorter the time period, the more uncertain any determination of energy will be.

Accordingly, using the current mathematical conventions, such calculations of acceleration will never be done "beyond all reasonable doubt", because the current convention is to allow the unintelligible (infinite) to be a part of the mathematical representation..

Quoting Metaphysician Undercover

The concept of "acceleration" involves a fundamental philosophical problem. Acceleration is the rate of increase of velocity. So if an object goes from being at rest, to moving, there is a brief period of time where its "acceleration" is necessarily infinite.

Show your math.

Reply to Metaphysician Undercover You're overthinking it a little bit. Regardless of philosophical issues, we can in fact experimentally verify, to some reasonable degree of precision, that bowling balls and pool balls both accelerate toward the ground when dropped. If you have philosophical problems with the concept of acceleration, you should separate that from your ability to look at that evidence and see what does, in fact, happen

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Reply to Metaphysician Undercover Reply to tim wood Reply to flannel jesus Reply to wonderer1
Tim, Flannel, and Wonderer beat me to the punch here. Any statement in the form "such-and-such a person observed X at such-and-such place & time" is either true (corresponds to reality) or false (does not correspond to reality).
Remember the verb here is "observed".

Quoting EricH

" **2 " means raised to the second power (i.e. squared). So " **3 " means raised to the third power, etc. This is standard scientific notation.

I've never seen "**" used as a symbol for the powers functions. I think the standard is "^", e.g. 5^2 = 25. In my experience, computer programs will accept that as input.

Reply to T Clark there are programming languages where ** means exponentiation. It's not as common as ^ but it's not unheard of either.

My mobile keyboard has exponent numbers. 2² = 4

Reply to T Clark
Hah - I'm showing my age. We used that in Fortran programming. It's somewhat obsolete now but can still see it used occasionally. E.g. here you'll have to scroll down a bit to see this:

"Exponents are given with a double asterisk, such as "3**2" (three to the second power). "

Note to self: use ^ in the future to represent exponentiation. :roll:

Quoting EricH

Hah - I'm showing my age.

Hah - I took Fortran during my freshman year in college in 1970. Timesharing and paper tape on a state-of-the-art mainframe.

Reply to T Clark You came in later. I had to use punch cards - but graduated to paper tape.

Quoting flannel jesus

2² = 4

I don't know how to do that on my keyboard, but now that you've shown the way I can cut & paste from your example. :clap:

BTW that was paper from Einstein about his thoughts on aether was very cool - thanks for that.

And now we wait to see what mu will come up with next.

Quoting wonderer1

Show your math.

What math? It's a philosophical problem, one which mathematics has not resolved. Look, there's a point in time, when a body at rest becomes a body accelerating. The body changes from being at rest, to being in motion at some point in time. Since the rate of increase of velocity (acceleration) is expressed as over a period of time, at this point in time, when the body changes from being at rest to being in motion, the rate of increase must be infinite because it's a number expressed over zero, x/0.

Quoting flannel jesus

Regardless of philosophical issues, we can in fact experimentally verify, to some reasonable degree of precision, that bowling balls and pool balls both accelerate toward the ground when dropped. If you have philosophical problems with the concept of acceleration, you should separate that from your ability to look at that evidence and see what does, in fact, happen

Yes of course, such objects accelerate. They must, in order to get from zero velocity to having some velocity. The problem is that we as human beings, do not have a very accurate understanding of acceleration. Our mathematical representation of it is very problematic. Read the following: https://en.wikipedia.org/wiki/The_Analyst

Notice that the article says that Berkeley's criticism of Newton was resolved with the concept of "limits". But this really doesn't solve the problem of acceleration because it places zero as a boundary, limit, which is never obtained. So the principle utilized is that there is no point in time when the object changes from being at rest to being in motion, because an infinite amount of time would pass before the boundary is crossed. So the crossing of that boundary, between rest and motion is never actually obtained by the mathematical representation.

It is this same proposition, which makes calculus logically rigorous, which also leads to the uncertainty principle, by allowing this "infinite" into the mathematical representation, and having boundaries within the modeling which cannot be crossed. You determine the momentum (motion) or you determine the position (rest), whichever one you choose to make an accurate representation of, the other approaches the boundary (infinite uncertainty).

.Quoting tim wood

Why don't you try answering his question?

I could not answer EricH's question because the presumptions which the question was based on were false. He said "I think you would agree that that is a true statement". I could not agree that it was a true statement, for the reasons I gave. He cited a measurement, and I explained that there is a measurement problem which did not allow me to agree that his measurement was "true". Then EricH tried to say that such a complex measurement was just an observation, which it clearly is not. That makes two false presumptions. What kind of inquiry is that, asking a loaded question with two false presumptions. That's like asking me 'did you stop beating wife, again?'.

Now flannel jesus gave me a better example of "an observation". Flannel said that heavy balls when dropped, accelerate toward the ground. I agree that they "must accelerate", because they go from being held to being in motion. But this is not an observation, it's more like a conclusion of logic. I do not notice the ball accelerating when I drop it, but I conclude that it must accelerate, because it goes from zero to having some velocity.

Now EricH's question concerned the relationship between "truth" and "understanding". EricH asked if I could agree to the truth of something without any understanding of what I was agreeing to the truth of. I'm sure many people could agree to the truth of something without any understanding of it, if this agreeing is done on faith, like the way that some religious people agree to the truth of God for example. But I am not prone to such agreements, I want to understand first, before I agree.

Regardless, this is irrelevant to the point I was making. I said "truth" implies understanding. But for someone to say "I agree that this is true", and for it to actually be true, are two different things. So "I agree that X is true" does not imply understanding in the way that truth itself implies understanding.

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Quoting Metaphysician Undercover

Yes of course, such objects accelerate. They must, in order to get from zero velocity to having some velocity. The problem is that we as human beings, do not have a very accurate understanding of acceleration. Our mathematical representation of it is very problematic. Read the following: https://en.wikipedia.org/wiki/The_Analyst

Notice that the article says that Berkeley's criticism of Newton was resolved with the concept of "limits". But this really doesn't solve the problem of acceleration because it places zero as a boundary, limit, which is never obtained. So the principle utilized is that there is no point in time when the object changes from being at rest to being in motion, because an infinite amount of time would pass before the boundary is crossed. So the crossing of that boundary, between rest and motion is never actually obtained by the mathematical representation.

All of that is very intriguing but also entirely beside the point.

Quoting tim wood

In 1966, Abraham Robinson introduced Non-standard Analysis, which provided a rigorous foundation for working with infinitely small quantities. This provided another way of putting calculus on a mathematically rigorous foundation, the way it was done before the (?, ?)-definition of limit had been fully developed.

I already told you the problem with the "rigorous" solutions. They are not real solutions because they allow "infinite" which is fundamentally unintelligible, as indefinite, into the mathematical representations. So any mathematical model employed, using these axioms which are designed to produce a "rigorous foundation" will have indefiniteness, which is a form of unintelligibility, built into it.

This is the problem with "formalism" (https://en.wikipedia.org/wiki/Formalism_(philosophy_of_mathematics)) in general. In its attempt to exclude the problems involved with applying the ideal (mathematical principles) to the material (physical) world, complete with accidents which appear as indefiniteness, formalism allows the indefiniteness (unintelligibility) to inhere within the formal (logical) structure itself. The result is that the source of unintelligibility (which inevitably arises in application), is impossible to isolate and identify.

If you do not understand this, then so be it. I will not try to explain, because I've done so numerous times on this forum, and I've come to respect that those who do not understand this are in that position because they deny the issue, and refuse to accept it as a real problem. They perceive that mathematics is very useful, and cannot apprehend the possibility that it could have problems. So it's generally a misunderstanding which is supported by a closed mind, and I am incapable of influencing people like you to open your minds.

Quoting tim wood

And it is equally clear that, short as the article is, you did not understand any of the rest of it either. "Berkeley did not dispute the results of calculus; he acknowledged the results were true. The thrust of his criticism was that Calculus was not more logically rigorous than religion. Berkeley concluded that the certainty of mathematics is no greater than the certainty of religion." Berkeley was writing as a Christian apologist.

Yes, what I tried to explain is that the type of "truth" that Berkeley is talking about here is a faith based truth. It is "truth" in the sense of coherence theory. If there is coherency within the logical system it produces truth. This is why I as well, do not dispute the usefulness of things like relativity theory, and calculus. The problem is with the "false", in the sense of correspondence theory, principles which the "free-thinkers" in Berkeley's words, employed. The "free-thinkers" we can understand as the pure mathematicians who dream up mathematical axioms. The problem is that there is no requirement that any mathematical axioms be "true" in the sense of correspondence. And if the axioms prove to be useful they are accepted, and used, regardless of truthfulness (correspondence). Now we all know that the soundness of any logical argument relies on the soundness of the premises (mathematical axioms in this case), so if you prefer, we can replace "truth" with "sound", and analyze how sound the supposed "rigorous" logic is.

In this case the subject was "fluxions" (https://en.wikipedia.org/wiki/Fluxion). According to the Wikipedia entry, this concept was central to the disagreement between Newton and Leibniz. If you have not studied this, principal disagreement between Newton and Leibniz concerned the relative importance of Newton's "momentum", as mass times velocity, and Leibniz' "vis viva" (https://en.wikipedia.org/wiki/Vis_viva) as mass times velocity squared. As it turned out, each is important in its own way, but Leibniz' principle needed be adapted by a coefficient of a half.

Quoting tim wood

Any claim of yours, then, of any problem with the maths in question here, whether mathematical, philosophical, or metaphysical, is ignorant, stupid, self-serving, and that you used it to evade a fair question on your inconsistent usages of "truth," I call vicious.

Uh huh. As I explained, I avoid your questions because I apprehend them as rhetorical. Your questions are presented not for the purpose of finding a point of mutual agreement, from which we can proceed in a rational inquiry, but they are designed for the purpose of opening up a point of attack. And when I refuse to answer, you are reduced to ad hominem, like above, demonstrating that you are overwhelmed by emotional weakness.

Quoting tim wood

These are incompatible. Reconcile them!

I do not see the incompatibility. To represent reality in the way of correspondence (truth), requires necessarily that one has some understanding of the reality being represented. Therefore "truth" in the sense of correspondence, implies understanding.

Quoting Metaphysician Undercover

Regardless, this is irrelevant to the point I was making. I said "truth" implies understanding. But for someone to say "I agree that this is true", and for it to actually be true, are two different things. So "I agree that X is true" does not imply understanding in the way that truth itself implies understanding.

I think it's incredibly feasible to agree to the truth of something without fully understanding it.

Someone may not understand motion, because intuitively they keep coming back to zenos paradox. But even if they don't understand it, they can agree that, for example, This car moved relative to me (or I moved relative to the car), or other such statements.

The same is true for the example given before about acceleration. You may not understand or even philosophically agree with certain aspects of acceleration mathematically, but without that understanding you can still acknowledge observations that say, "after dropping the bowling ball, it was going at about 9.8m/s downward after 1 second , and it was going about 19.6m/s downward after 2 seconds , and it was going about 29.4m/s downward after 3 seconds".

You don't need to understand acceleration to agree with some basic observable facts about how bowling balls fall.

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Quoting Metaphysician Undercover

To represent reality in the way of correspondence (truth), requires necessarily that one has some understanding of the reality being represented. Therefore "truth" in the sense of correspondence, implies understanding.

Here is the plain language definition per wikipedia
"In metaphysics and philosophy of language, the correspondence theory of truth states that the truth or falsity of a statement is determined only by how it relates to the world and whether it accurately describes (i.e., corresponds with) that world."

Now you are introducing the notion of understanding into the mix - and it's not clear to me what you mean here. If by the word "understanding" you mean that a statement is grammatically and syntactically correct and expresses a thought/notion that could potentially be real? Then that is trivially correct.

"My friend John is 5 feet 11 inches tall (within the limits of accuracy of my measuring apparatus)" is a true statement.

"My friend John is 5000 feet 11 inches tall (within the limits of accuracy of my measuring apparatus)" is a false statement.

But if by "understanding" you mean something more than our shared understanding of the plain language meaning of words, then this raises all sorts of questions - what do you mean by "understanding"? Can we ever fully understand anything at all? Warning! Warning! Infinite regress ahead!

That said, perhaps you are using a variation of the standard definition/usage of correspondence theory? That's fine - there is nothing wrong with this. If you go to Stanford the theory of correspondence comes in a bewildering variety of flavors - and maybe you are using one of these variations?

Regardless of all this, I refer you to flannel's last comment:
Quoting flannel jesus

You don't need to understand acceleration to agree with some basic observable facts about how bowling balls fall.

Quoting Metaphysician Undercover

What math? It's a philosophical problem, one which mathematics has not resolved. Look, there's a point in time, when a body at rest becomes a body accelerating. The body changes from being at rest, to being in motion at some point in time. Since the rate of increase of velocity (acceleration) is expressed as over a period of time, at this point in time, when the body changes from being at rest to being in motion, the rate of increase must be infinite because it's a number expressed over zero, x/0.

That's what I'm asking you, "What math?"

You keep bringing up mathematical issues, such as infinity and division by zero, as if they are magic words meant to distract from your inability to explain why they are of relevance.

It's starting to appear as if you don't know how to apply math to the situation. (Not that there is anything wrong with that.)

Quoting flannel jesus

I think it's incredibly feasible to agree to the truth of something without fully understanding it.

Sure, but the condition was understanding, not "fully" understanding. And, I really do not understand what "fully understand" would mean, because sometimes when I think that I understood something it turns out that I really did not. So "fully understand" would be a difficult concept to understand..

Quoting flannel jesus

The same is true for the example given before about acceleration. You may not understand or even philosophically agree with certain aspects of acceleration mathematically, but without that understanding you can still acknowledge observations that say, "after dropping the bowling ball, it was going at about 9.8m/s downward after 1 second , and it was going about 19.6m/s downward after 2 seconds , and it was going about 29.4m/s downward after 3 seconds".

No, that's the point, I would not agree to this. I would want to see the measuring technique, the justification for this claim, that "it was going at about 9.8m/s downward after 1 second", etc.. What I said, is that some others might accept this, as a matter of faith in some principles they hold, but I am not inclined to accept things on faith. And the point is that I do not believe that accepting somethin completely on faith is really a judgement of truth. I would say that faith provides a type of understanding, but not all types of understanding necessitate truth. I would argue that "truth" implies a special type of understanding

So if you told me that it was going " 9.8m/s downward after 1 second", and I said yeah, sure, I believe you, I would not consider that I've judged what you have said to be true, unless I have some understanding as to why you said that. If I believe that I understand why you said that, then I would say that I accept it as truth. If I have no understanding whatsoever, of why you said that, yet I still accept it, then I accept it for some reason other than believing that it is true. Many statements are accepted for reasons other than the belief that they are true.

Quoting tim wood

So, the solutions offered as such by mathematics are not solutions? What do you imagine mathematics and solutions to be?

Mathematics may provide some solutions sometimes, but in respect to the problem being discussed, the problem of acceleration, mathematics does not provide a solution. What it does is provide a "work around",. It veils the problem so that it disappears in some situations, so long as the temporal duration is not too long or too short, but then it simply reappears in other situations. As I said, the problem now reappears as the uncertainty principle, so the mathematics has clearly not resolved the problem.

Quoting EricH

"In metaphysics and philosophy of language, the correspondence theory of truth states that the truth or falsity of a statement is determined only by how it relates to the world and whether it accurately describes (i.e., corresponds with) that world."

Now you are introducing the notion of understanding into the mix - and it's not clear to me what you mean here. If by the word "understanding" you mean that a statement is grammatically and syntactically correct and expresses a thought/notion that could potentially be real? Then that is trivially correct.

Let's consider the definition you provided, truth concerns how a statement relates to the world. Do you not agree, that in order to establish a relationship between a statement and the world, there are certain requirements such as 1) understanding the meaning of the statement, 2) understanding the world which the relationship is to be established with. Without these two types of understanding how could there possibly be a relationship between the statement (a bunch of letters), and a thing which is called "the world"?

Quoting EricH

But if by "understanding" you mean something more than our shared understanding of the plain language meaning of words, then this raises all sorts of questions - what do you mean by "understanding"? Can we ever fully understand anything at all? Warning! Warning! Infinite regress ahead!

I do not know what you mean by "shared understanding". To me, "understanding" is something personal. I might understand you, and you might understanding me, but this does not mean that we have a shared understanding, because each of us has a different understanding.

here's what my OED has for "understanding", and I think we could pretty much choose any of these. 1 a) the ability to understand or think, intelligence. b) the power of apprehension; the power of abstract thought. 2) an individual's perception or judgement of a situation etc. 3) an agreement; a thing agreed upon, esp. informally. Note that "understand" is defined first as perceive the meaning of (words, a person, a language, etc.) and second, perceive the significance, explanation or cause of.

Quoting wonderer1

It's starting to appear as if you don't know how to apply math to the situation. (Not that there is anything wrong with that.)

I really do not believe that there is a way to successfully apply math to the situation. That's the point, it's a philosophical problem which math cannot resolve. math has its limits, and there are many problems which it cannot resolve.

Quoting Metaphysician Undercover

No, that's the point, I would not agree to this. I would want to see the measuring technique, the justification for this claim, that "it was going at about 9.8m/s downward after 1 second", etc.. What I said, is that some others might accept this, as a matter of faith in some principles they hold, but I am not inclined to accept things on faith.

What's all this talk about faith? You think people came up with the 9.8 number on faith?

Quoting flannel jesus

What's all this talk about faith? You think people came up with the 9.8 number on faith?

No, I don't think it was produced from faith. But if you told me the thing was going 9.8 metres per second after a second, and I had absolutely no understanding of how you came up with that number, but still I believed you, wouldn't this belief be based in nothing other than faith?

Reply to Metaphysician Undercover why is that the scenario you invented, rather than a scenario where I show you the numbers and how I got them?

Reply to Metaphysician Undercover Reply to EricH metaphysician, please recall that this all started with us imaging a scenario where these measurements were done to your satisfaction. Now, whether you think they're actually capable of being done to your satisfaction is entirely different question from your ability to imagine a scenario where they were done to your satisfaction.

If it's inconceivable to you that these measurements could be done, by you or anyone else, to a satisfactory degree, then I would propose that you are immune to science.

I'm also genuinely quite amazed at the conspiratorial nature of your approach to acceleration due to gravity. Do you really not think there's sufficient evidence for it? Are the physicists of the last hundreds of years incompetent or just lying? How did we manage to make it to the moon, or send rovers to Mars, if we don't even grasp the very basics of gravity? I can't tell how sincere you are about all this.

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Quoting flannel jesus

Now, whether you think they're actually capable of being done to your satisfaction is entirely different question from your ability to imagine a scenario where they were done to your satisfaction.

I thought I explained this . The current state of "mathematics", the axioms and rules which are the current conventions, make it impossible that this could be done to my satisfaction. So I cannot imagine this scenario. You are asking me to imagine something which I am saying is impossible for me to imagine. For me to imagine this being done to my satisfaction would be to imagine it being done with something other than "mathematics".

This is very analogous to the issue with the aether in an inverse way. The nature, characteristics and properties, of "the aether" are dictated by definition, because we have no sense perception, empirical data of it. So, for the M-M experiment it was stipulated that the aether was a separate substance from the massive bodies, therefore the bodies would make a disturbance in the aether, a sort of wake. The experiments showed no such disturbance, therefore there is no "aether", as defined.

But what the experiment really indicates is that the dictated properties of the aether are incorrect. And of course this is consistent with empirical evidence, because we see that light and electromagnetism passing right through many bodies, therefore the aether must also exist within the bodies, and not be a separate substance.

So in the case of "mathematics", above, the word refers to something very real, supported by much empirical data, and usage of axioms and rules. So we have a very real thing being referred to, which we can look at, and see the properties of. This reality dictates the definition of the thing, mathematics. I'll call it a tool. Now, I look at this tool, and say that it is simply incapable of doing the job to my satisfaction. The tool referred to by "mathematics" cannot do the job I want done, and so I need a different tool. Therefore, either we can alter this tool to make it useful to my task, or we can come up with a new tool to do the task.

In the case of "aether", the situation is inverted. We cannot see, or otherwise perceive what we are looking for. We know from logic that it is there, whether it best be represented as "aether" or as "field", or whatever term. Now if we adhere to the defining terms of aether, which stipulate that aether is a substance separate from the substance of bodies, then we can know that there is no aether. But this conclusion does not help is to solve the problem. We still need to identify the medium, and learn its properties. That there is no "aether" in this case does not mean there is no medium, it just means the defining features of the medium were wrong. Likewise, when I say "mathematics" is incapable of resolving a specific problem, I do not mean that the problem is irresolvable. I mean that the defining feature of mathematics make it so that mathematics cannot resolve the problem. Therefore we need to either change the defining features of mathematics (as in the case of aether), which in this case means actually changing the tool, or, we need to come up with another tool (with a different name), like in the case of "aether", we'd give the medium a different name. .

Quoting flannel jesus

I'm also genuinely quite amazed at the conspiratorial nature of your approach to acceleration due to gravity. Do you really not think there's sufficient evidence for it? Are the physicists of the last hundreds of years incompetent or just lying? How did we manage to make it to the moon, or send rovers to Mars, if we don't even grasp the very basics of gravity? I can't tell how sincere you are about all this.

I believe that what you call "acceleration due to gravity" is not well understood by human beings. And, I explained that the fact that people have the capacity to predict motions of bodies does not imply that the true nature of those motions is well understood. So questions like "how did we manage to..." have little if any bearing on this issue. The capacity to do things does not imply that the doer understands what is being done; that is what Socrates demonstrated. In fact, Socrates demonstrated the very opposite, in no cases of people doing things, did the people adequately understand what they were doing.

Quoting tim wood

But we know you, MU - and these others don't although they're learning - that you do not agree even that 2+2=4.

This is an intentional misrepresentation. I do believe 2+2=4, and I've told you this before. What I've argued against, and strongly do not believe is that "2+2" represents the very same thing as "4". So what I do not believe is that "=" means "is the same as" which is what is argued by many here at TPF.

Quoting tim wood

Mathematics, as used in the sciences at least, is the language used to try to describe with some rigor, precision, accuracy, and consistency what is happening in nature, and when done well, called a solution

OK, we have here: "mathematics...is the language used to try to describe.. and when done well, called a solution". Notice your use of "try", and "a solution" only occurs when "done well". And, as I've described using English, one of very many languages used to describe what is happening in nature, there are aspects of nature (such as acceleration) which cannot be described by the current grammar of this language called "mathematics". So, as I've pointed out, when people use mathematics to try to describe these aspects of nature, their attempts fail, therefore this ought not be called "a solution".

Quoting tim wood

Btw, as you well know there are at least several mathematicians who post here, and a characteristic of their work is the effort to demonstrate and make clear their own arguments and points about their topic, to educate and contribute to a general clarity and understanding. You on the other hand pontificate without substance, demonstration, evidence, clarity, or proof. And while you claim to understand that this is a philosophy site, you consistently refuse any substantive reply to the question, "How do you know?"

Some mathematicians really demonstrate that they do not know what is being done with mathematics. They insist on silly principles such as the one mentioned above, that "=" means "is the same as". This indicates that they really have a very deep misunderstanding of what an equation is and what is being done by mathematicians with the use of equations. This is exactly what Socrates demonstrated many years ago, that when people are doing things, they really cannot accurately describe what they are doing, and this means that they do not know what they are doing.

Quoting tim wood

Ultimately you're a waste of time, and I would like you to stop it!

Why do you keep asking me questions if you want me to stop posting? Your use of language demonstrates a base irrationality.

Reply to Metaphysician Undercover Can you give an example of a statement involving the mathematical measurement of some physical property of an object that you would consider to be a true statement - per the correspondence theory of truth?

Quoting Metaphysician Undercover

I thought I explained this . The current state of "mathematics", the axioms and rules which are the current conventions, make it impossible that this could be done to my satisfaction. So I cannot imagine this scenario. You are asking me to imagine something which I am saying is impossible for me to imagine. For me to imagine this being done to my satisfaction would be to imagine it being done with something other than "mathematics".

This seems like you're still overthinking it. You're focusing so much on abstract mathematics and not enough on concrete measurements. Galileo didn't discover acceleration due to gravity via abstract mathematics, he measured it. If you can't imagine measurements, then let me do the imagining for you. I don't believe it's particular challenging.

I've set up an apparatus to measure the distance a cube is falling over time - it's just a really tall building (let's say 100m), with a bunch of measurements marked up its height, and a high speed camera to track how far it has travelled at every moment. Such a setup is actually pretty sufficient to get a good idea of this problem.

So, we start out by asking, how fast was it falling approximately at 1s? We look at our high speed footage and we measure is position at 0.9s and 1.1s. We find the positions are 3.97 and 5.93 respectively (measured in meters from the starting point). So we find out that in that 0.2s time frame, it travelled about 1.96m, which means it was going about 9.8m/s.

Then we ask, how fast was it going at 2s? So we do the same thing as before, we find it's position at 1.9s (17.7m) and 2.1s (21.62m). We calculate how fast it was going approximately over those 0.2s and it turns out it was going 19.6m/s.

We do the same thing for 3s, measuring it's position at 2.9s and 3.1s to be 41.24m and 47.12m, giving it a velocity of 29.4m/s.

We do the same thing for 4s, measuring position at 3.9s and 4.1s to be 74.58 and 82.42m respectively, giving it a velocity of 39.2m/s.

So we get all our results together, and quickly notice that every time a second passes, the cube seems to be traveling 9.8m/s faster than it was traveling the previous second.

Why are these sorts of measurements, and this sort of experiment, unimaginable to you? Are they still unimaginable to you now?

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Quoting EricH

Can you give an example of a statement involving the mathematical measurement of some physical property of an object that you would consider to be a true statement - per the correspondence theory of truth?

No, that's what Ive been arguing, we really do not know the true physical properties of objects. I think that's what the experimentation with Bell's theorem, discussed earlier in this thread, indicated.

Quoting flannel jesus

This seems like you're still overthinking it. You're focusing so much on abstract mathematics and not enough on concrete measurements. Galileo didn't discover acceleration due to gravity via abstract mathematics, he measured it. If you can't imagine measurements, then let me do the imagining for you. I don't believe it's particular challenging.

I think that this is a misrepresentation, and this is why were having difficulty coming to agreement here. We cannot directly measure acceleration, nor can we even directly measure velocity. Determinations of these require a multitude of measurements, with an application of mathematical principles, such as averaging. Because this process of averaging is a requirement for any determination of acceleration, these determinations are not properly called "measurements" but are better represented as logical conclusions, i.e. conclusions derived from the application of logical principles to some premises. The premises might be called measurements.

Quoting flannel jesus

So, we start out by asking, how fast was it falling approximately at 1s? We look at our high speed footage and we measure is position at 0.9s and 1.1s. We find the positions are 3.97 and 5.93 respectively (measured in meters from the starting point). So we find out that in that 0.2s time frame, it travelled about 1.96m, which means it was going about 9.8m/s.

According to what I expalined above, you have taken two measurements, the position at .9s and the position at 1.1s, applied some logic, and concluded the object was moving at 9.8m/s in the duration. Of course, if the object was actually accelerating during this time period, this is not a true representation. If the object was accelerating, its velocity was different at .9s from what it was at 1.1s. But your method concludes that the object was going at the same speed for the entire .2s period, and this is contradictory to the premise that the object is accelerating. So it's very clear to me that this method of averaging does not give a true representation, regardless of assertions that it does.

Quoting flannel jesus

So we get all our results together, and quickly notice that every time a second passes, the cube seems to be traveling 9.8m/s faster than it was traveling the previous second.

Why are these sorts of measurements, and this sort of experiment, unimaginable to you? Are they still unimaginable to you now?

Well, look what you have shown me. Between .9s and and 1.1s the object was moving at a constant speed. Then it accelerated between 1.1s and 1.9s. Then between 1.9s and 2.2s it moved at a constant speed again. And so on. How is this imaginable to you? It implies that the force (gravity) acted to accelerate the object over a period of time, then it quit acting on the object for a period of time (between .9s and 1,1s) when its velocity remained constant, then it acted again, then the force quit acting again, etc.. How is this imaginable to you? Why would the force stop and start acting in complete coincidence with the timing of your measurements, when the timing of your measurements is completely arbitrary?

Quoting tim wood

But you are dismissive of the map because it is not the territory, and that is an unseemly and unaccountable (on rational terms) error for someone like yourself.

No, I am dismissive of the map because it is misleading, as I clearly explain above, in this post. And, a misleading map gets people lost.

Quoting tim wood

As with the 2+2=4, you say that the 2+2 does not represent the same thing as 4, and of course it exactly represents the same thing as 4.

I disagree that "2+2" represents the exact same thing as "4", and you're very naive to believe this. I've explained why, elsewhere. If it did represent the exact same thing, equations would be completely useless. The left side of the "=" would necessarily represent the exact same thing as the right side, and the equation would do absolutely nothing for us. But of course, that's not how we use equations in practise, the left side always represents something different from the right side, and in working out why the two distinct things are equivalent we solve a problem.

Quoting tim wood

And I refute this thus: When they are doing something, are they doing that thing, or are they doing something else? If you had read a little more closely, you would have seen that Socrates did indeed find people who knew what they were doing, but not wise, because they, knowing something, thought that they knew more that they did, thus knowing something, but not wise. That is, the Oracle had told Socrates that he was the wisest, and Socrates had to discover that wisdom and knowledge are not the same thing.

Sorry, I do not follow your claimed refutation.

Quoting Metaphysician Undercover

And, a misleading map gets people lost.

Ah, the irony.

There are none so blind...

Reply to Metaphysician Undercover you're still over thinking everything. Or you're just immune to science.

Quoting Metaphysician Undercover

Well, look what you have shown me. Between .9s and and 1.1s the object was moving at a constant speed.

That's an assumption YOU made, not me. I said APPROXIMATE speed. I didn't say constant. I don't know why you would assume it's constant, the data doesn't say that.

If you insist on overthinking it, you should be very careful in your overthinking.

Quoting flannel jesus

Or you're just immune to science.

MU has as much as said that his mind is closed to the extent that he can keep it so:

Quoting Metaphysician Undercover

I, am an impenetrable fortress. Nothing, I repeat nothing, from that "external world" can infiltrate my defenses, and move me. All which exists within my mind comes from the inside. Thus is my reality.

There is however, a sense in which ideas come to my mind from somewhere other than my mind. Since they cannot penetrate through my fortress, and enter from the external, and "ghostly phenomena" is silly talk, I conclude that they enter my mind through "inner space". And since the ideas which enter my mind through inner space seem to be very similar to the ideas which enter your mind through inner space, I can conclude that we are very well connected through inner space.

Reply to wonderer1 I see. I suspected it was some situation like that, interesting that he just lays it out so explicitly.

Reply to tim wood Quoting flannel jesus

I said APPROXIMATE speed.

I think you've stated my case for me very well, flannel. "Approximate" with respect to a representation means near, or close to what is actually the case. This does not imply truth, but the contrary, it implies a lack, or deficiency of truth. So the fact of the matter is that we just do not have an accurate, precise, or truthful representation of what acceleration actually is. And that is exactly the deficiency which I've been claiming.

And here, Reply to tim wood thinks that this sort of approximation process provides for a "rigorous foundation". Rigorous: "strictly exact or accurate". I apprehend an implied contradiction between "approximate" and "rigorous".

Quoting Metaphysician Undercover

I think you've stated my case for me very well, flannel. "Approximate" with respect to a representation means near, or close to what is actually the case. This does not imply truth, but the contrary, it implies a lack, or deficiency of truth. So the fact of the matter is that we just do not have an accurate, precise, or truthful representation of what acceleration actually is. And that is exactly the deficiency which I've been claiming.

If you choose to reject all evidence you could see, then you will of course always have that deficiency. You seem very committed to that deficiency. Other people, luckily for the rest of us, seem more committed to finding stuff out.

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Quoting flannel jesus

If you choose to reject all evidence you could see, then you will of course always have that deficiency.

I don't see how this is relevant. I am not rejecting any visible evidence, I am describing deficiencies of mathematical logic.

Quoting tim wood

And this would be you, MU,

Completely false representation. Strawman.

Quoting tim wood

Perhaps you imagine your truths in carved adamantine mounted on polished-granite Doric columns in a Platonic space somewhere, and being thus inaccessible, dismiss truth as not having any world-function value, being itself Platonic. And so this is not a horse, that is not a chair, nor that a tree, but all these, and all else, just poor imitations such that no truth appertains to them. Well guess what, you're just plain wrong and wrong-headed, and the proof and evidence is all the world's work that gets done using all kinds of truths. If you disagree, then how does all the world's work get done if absent truth?

Sorry tim, I have no idea how this nonsense is in any way relevant. I've already explained how pragmatic principles are not necessarily truths. So your question has already been answered.

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Quoting Metaphysician Undercover

I don't see how this is relevant. I am not rejecting any visible evidence

You sure are, and you seem proud of it. That's your right, of course. Science doesn't speak to you, and you don't speak to it. I would say it's unfortunate that you would just remove all scientific knowledge from being a viable part of your own knowledge, but you seem happy enough with the decision.

I am increasingly thinking of 'truth' as a misleading and undefinable concept. For one thing, just because some statement are true, that does not provide a reason for postulating that there is a meaningful abstract noun 'truth'. 'True' is (at most) a predicate, an adjective modifying the proposition being discussed - making it a noun is simple reification. Defining 'truth' only creates a 'thing' that we can argue about. We can instead ask 'What does it mean for a proposition to be true?'. Secondly, in science, 'truth' was replaced by 'certainty' by Descartes, which was later replaced by 'confidence', reflecting the lack of total certainty of anything other than that, updating Descartes, 'there is thinking, therefore there is thinking'. Describing something as 8 ft long means that we expect, with 95% confidence, that the length of the 2x4 is between 8 - delta and 8 + delta feet long, where delta is situation specific, and can be either explicit or specified.

Interesting discussion of how we characterise objects in 'Women, Fire and Dangerous Things' by Lakoff. A tree is recognised as a tree because it is similar to objects that have been previously characterised as trees.

Quoting tim wood

I get it. No two things are ever the same. Nothing is ever measured exactly, nor can it be. But if I want to buy a pallet of 8' 2x4s per spec., I will get them, "rigorous and exact" per specification. And will it then be true to say they are 8' 2x4s, and will they truly be 8' 2x4s? Of course they will. And you may come in and say, "Oh no, they're not the same and there is no way to tell if they're even 8' 2x4s: this one is three one-millionths of an inch longer than that one, and that one,...& etc."

Measurement of static objects is not the same as measurements of motions, so your example is not analogous, as the problem I was discussing, the issue of acceleration, does not occur. As for the 2x4s being "the same", they are clearly not the same in any rigorous application of the law of identity. They are similar, as things of "the same type" are similar.

Quoting tim wood

And you will insist that you are correct, and I hold there are three responses to you. First, that you're wrong. By the applicable criteria, they are 8' 2x4s, period. Second, that you are in a very narrow sense correct, but uselessly so. With the lumber, for example, your argument is just a pig-in-the-parlor, the wrong animal in the wrong place at the wrong time. Third you are vacuously correct, in that if you insist on one inappropriate standard, then all are equally valid. Then you are headfirst down a rabbit-hole trying to say something, anything, intelligible and correct, but you have made that either empty or impossible.

Here you contradict yourself. You say I am "vacuously" correct, and you say I am "uselessly" correct, Also you say I am "wrong". Your claim that I am wrong is not justified though. That "they are 8' 2x4s, period" means that they are all the same type, just like we are all human beings. It does not mean that they are all the same. Do you not understand the difference between being of the same type, and being the same thing?

And, the fact that you judge my correctness as unimportant or insignificant, is irrelevant to the fact that I am correct. You, like flannel jesus, simply refuse to respect the evidence which demonstrates that this problem in specific circumstances, has a significant effect on certainty. And as Reply to Richard Goldstein points out, certainty is very important to us.

Quoting flannel jesus

You sure are, and you seem proud of it. That's your right, of course. Science doesn't speak to you, and you don't speak to it. I would say it's unfortunate that you would just remove all scientific knowledge from being a viable part of your own knowledge, but you seem happy enough with the decision.

Hey, you gave me the example, as "evidence", and I showed complete respect for that evidence. The I showed you the problem, which you dismissed as a matter of approximation. That approximation becomes a significant problem under specific circumstances. So it's not me who is rejecting the evidence, it is you who is rejecting the evidence. You gave me the example, I showed you the problem within your example.

If you are interested in continuing, and examining the implications of this problem we could. Tim, above, seems to think that identifying such problems is useless, "vacuous", but as I said earlier, this very problem produces the Fourier uncertainty which forms the base of "the uncertainty principle". So denying that there is a problem, is really a denial of the evidence, and claiming that the problem is insignificant is a refusal to accept the evidence.

Quoting Metaphysician Undercover

That approximation becomes a significant problem under specific circumstances.

No, it really doesn't. If you know the location of something at 1s, and the location of the same thing at 2s, you made the logical leap of assuming that means it had a constant speed over that duration, rather than the much more carefully thought out concept that you have the AVERAGE speed over that duration. You're making careless logical leaps and then acting as if you've disproven physics.

It doesn't matter what problem you think there is with the example, if the measurements are real measurements that real people really obtained. These are, in fact, the sort of realistic measurements one could make to verify how the speed of a falling ball changes over time.

I'd only be interested in examining the implications with you on the condition that you accept the measurements as real raw data.

If you think it's impossible for that to be valid raw data, then feel free to show me what the raw data of a ball falling really looks like.

Quoting Metaphysician Undercover

No, that's what Ive been arguing, we really do not know the true physical properties of objects. I

This is not the Correspondence Theory of Truth - you have introduced the metaphysical concept of truth into the mix. If you and I are traveling in a car together and the digital display shows that the car is going 60 mph and I utter the statement "The car is going 60 mph according to the speedometer". then that is a true statement. And if you are in the back seat looking over my shoulder and say "The speedometer shows that the car is going 60 mph". then we have a mutual shared understanding and agree.

Whether the speedometer is accurate or not is irrelevant to whether the statement is true or false.

Quoting flannel jesus

No, it really doesn't. If you know the location of something at 1s, and the location of the same thing at 2s, you made the logical leap of assuming that means it had a constant speed over that duration, rather than the much more carefully thought out concept that you have the AVERAGE speed over that duration. You're making careless logical leaps and then acting as if you've disproven physics.

As you said already, that "AVERAGE speed" is just an approximation. It does not accurately represent the motion of the thing over that period of time, because during that period of time the thing was accelerating. That is exactly what I am arguing, we do not have an accurate representation of acceleration. To represent a thing's average speed in the time between 1s and 2s, is not a good representation of acceleration.

Quoting flannel jesus

It doesn't matter what problem you think there is with the example, if the measurements are real measurements that real people really obtained. These are, in fact, the sort of realistic measurements one could make to verify how the speed of a falling ball changes over time

Sure, they are "real measurements, but the fact remains, that representing a thing's average speed over a period of time, does not provide a good representation of acceleration.

Quoting flannel jesus

I'd only be interested in examining the implications with you on the condition that you accept the measurements as real raw data.

I accept that these measurements can be made. But as I said, the problem is with the mathematical way of calculating. So the real question is, are you ready to accept the flaws which I have pointed out. It seems to me, like you just want to try to explain them away, by choosing different words. First you used "approximate", then when I showed you the problem with approximation, you then switched to "average".. It really makes no difference which words you choose, because the problem is very real, and you cannot make it go away by using different words to describe it.

Quoting EricH

This is not the Correspondence Theory of Truth - you have introduced the metaphysical concept of truth into the mix. If you and I are traveling in a car together and the digital display shows that the car is going 60 mph and I utter the statement "The car is going 60 mph according to the speedometer". then that is a true statement. And if you are in the back seat looking over my shoulder and say "The speedometer shows that the car is going 60 mph". then we have a mutual shared understanding and agree.

Whether the speedometer is accurate or not is irrelevant to whether the statement is true or false.

I disagree. If the speedometer is faulty, then the car is not going 60mph according to the speedometer. The speedometer is incapable of determining the speed of the car, therefore the reading does not accord with the speed and there is no such thing as 'the speed of the car "according to the speedometer". Your use of words is just trickery Eric. Face the fact, when the speedometer is broken there is no such thing as the speed of the car according to the speedometer.

Reply to Metaphysician Undercover
OK I'll modify the statement to meet your exacting standards. Instead of this:.

Quoting EricH

"The car is going 60 mph according to the speedometer"

we'll say this

"The digital readout on the speedometer shows 60 mph"

:yawn:

Quoting Metaphysician Undercover

So the real question is, are you ready to accept the flaws which I have pointed out.

You haven't pointed out any logical flaws. You've made careless logical leaps that I've pointed out, and you haven't accepted the logical flaws in what you said .

Do you accept that leaping to "constant speed" was a careless logical flaw?

Quoting Metaphysician Undercover

Well, look what you have shown me. Between .9s and and 1.1s the object was moving at a constant speed. Then it accelerated between 1.1s and 1.9s. Then between 1.9s and 2.2s it moved at a constant speed again.

I won't accept your criticism that I said it's an average speed while you're out here making completely absurd conclusions like it's a constant speed. Let's get that out of the way first.

Quoting EricH

we'll say this

"The digital readout on the speedometer shows 60 mph"

This says nothing about the problem we're discussing.

Quoting flannel jesus

You haven't pointed out any logical flaws. You've made careless logical leaps that I've pointed out, and you haven't accepted the logical flaws in what you said .

Do you accept that leaping to "constant speed" was a careless logical flaw?

Sure. "constant speed" was a bad use of terms, But "approximate", and "average" do not imply that the speed was anything other than constant. You have provided no representation of the movement of the object during that time period. This is the problem, you have no indication of what the object was actually doing during that time period, no representation of 'the movement of the object'. You have provided two different positions at two different times, and the object was said to be moving as it past each position, that's all Now you insist that "constant} is not a proper representation of the object's speed during that time, but you have provided no representation of a non-constant motion.

That is what I say is the problem, there is no representation of a non-constant speed. Newtonian mechanics takes constant speed (uniform motion) for granted, in his first law. A change to constant speed requires an application of force. But because uniform motion is taken for granted, the application of force cannot be properly understood. It is just represented as a change to uniform motion.

So. let's proceed as you suggest, and consider that "constant speed", or "uniform motion" is a careless logical principle. It does not actually represent anything real in the universe. It's just an ideal, and real motions are always changing all the time, so that this ideal is not a proper representation of any real motion.

Now look what you gave me.

Quoting flannel jesus

So we find out that in that 0.2s time frame, it travelled about 1.96m, which means it was going about 9.8m/s.

You provide two different positions and the thing was moving as it passed each position, and you've provided a time of passing, that's all Now you insist that "constant speed" is inappropriate for the duration. That's fine, as explained above, constant speed is just an ideal, and motion is really changing all the time. But all you have is "it was going about 9.8m/s" during that time period:. This indicates one speed during that entire time period, and we agree that "constant speed" is an inadequate representation. Do you not also agree with me, that "going about 9.8m/s" is a completely inadequate representation of what is actually going on in that time period?

Quoting Metaphysician Undercover

Sure. "constant speed" was a bad use of terms

I really respect you for saying this, wonderful.

Quoting Metaphysician Undercover

But "approximate", and "average" do not imply that the speed was anything other than constant.

That's right, they don't imply that, that's part of why they work. They don't imply much at all. They're just simple truths given the data, no extra implication.

Quoting Metaphysician Undercover

Now you insist that "constant} is not a proper representation of the object's speed during that time, but you have provided no representation of a non-constant motion.

I didn't say it's not constant either, you're still making logical leaps. Slow down.


Quoting Metaphysician Undercover

But all you have is "it was going about 9.8m/s" during that time period:. This indicates one speed during that entire time period, and we agree that "constant speed" is an inadequate representation. Do you not also agree with me, that "going about 9.8m/s" is a completely inadequate representation of what is actually going on in that time period?

Inadequate compared to what? Google "how to calculate average speed". The first result gives me "It is calculated by dividing the total distance something travels by the total amount of time it spends traveling." In fact many Google results give me that. That's what I was trying to calculate. I don't see why it's inadequate, it achieved the exact goal that I wanted it for. I now have the average speed for the .2 seconds timeframe around the 1 second mark, the 2 seconds mark, etc. That's what I wanted, that's what I got. It's perfectly adequate for achieving the goal I was hoping to achieve.

Quoting Metaphysician Undercover

Sure. "constant speed" was a bad use of terms, But "approximate", and "average" do not imply that the speed was anything other than constant. You have provided no representation of the movement of the object during that time period.

Everyone else who has been involved in this discussions understands that the ball is accelerating continuously in the scenario under consideration. Your lack of comprehension is not caused by the other people in the discussion.

Quoting Metaphysician Undercover

This says nothing about the problem we're discussing.

One step at a time. Do you acknowledge that "The readout on my speedometer shows 60 mph" is a true statement per the CToT?

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Quoting flannel jesus

Inadequate compared to what?

It's inadequate as a representation of what is actually going on. So it is inadequate in comparison to what a true representation of what is actually going on would provide. "Average" is simply not an accurate or rigorous representation of what is the case. When it is used as a representation of what is the case, it is a sort of estimation. In your own words, it is "approximate".

Consider that to "average" is to take many times, and express it as one time, that one time being the average of the many. So for example, if the sun rises between 6;00 and 6:30 for twenty days in a row, and you take the average, it would be 6:15. The you would say that the average over all those days is 6:15. But obviously, averaging is a completely inaccurate way of trying to represent what is actually going on. Now, in your .2 duration of time, there are numerous different points of time, each of which has the thing moving at a different speed from the others, and you come up with one speed which, 9.8m/s, which is supposed to apply to all those points of time. Just like in the example of the different sunrise time, giving the same value to numerous different times, as the average of those times, is obviously extremely inaccurate.

Quoting flannel jesus

I don't see why it's inadequate, it achieved the exact goal that I wanted it for. I now have the average speed for the .2 seconds timeframe around the 1 second mark, the 2 seconds mark, etc. That's what I wanted, that's what I got. It's perfectly adequate for achieving the goal I was hoping to achieve.

It may be what you wanted, but it's useless as a means to resolving the problem I'm trying to bring to your attention. You now have a period of time, .2 seconds duration, with an average speed of 9.8 m/s during that period of time. How do you think that a determination of an average speed is at all useful toward representing acceleration?

Remember what you said to me "constant" is "a careless logical flaw". Therefore we cannot assume that the acceleration during this time period is in any way constant, because that would be a careless logical flaw. So how do you think that determining an average speed over a period of time would be at all useful toward making an accurate representation of the acceleration which occurred during that time frame?

Quoting wonderer1

Everyone else who has been involved in this discussions understands that the ball is accelerating continuously in the scenario under consideration.

This use of "continuously" is more accurately stated as "constantly", and that is what flannel has described as "a careless logical flaw".

Quoting EricH

One step at a time. Do you acknowledge that "The readout on my speedometer shows 60 mph" is a true statement per the CToT?

Sure, if that's what's there on the screen, then I agree, that's a true representation. The issue is one of interpretation though. Your claim was that this readout means that according to the speedometer the car is going 60mph. But that is not what that readout actually means, it's a faulty interpretation of what the readout means.

Quoting tim wood

MU apparently disqualifies naming. We cannot name anything because we do not know what it is.

Tim, we do not need to know what a thing is in order to name it. Just point to a thing, and assign a word, or words to it. Then the thing has a name even though there might be no one who knows what it is.

Quoting tim wood

Third, if MU is right, nothing can be said about anything - and MU, if he had any intellectual integrity, would content himself with just pointing, and otherwise remain silent.

Of course this is wrong too. After naming the thing we can say whatever we want about it, compare it to other things that have also been named, and so on. None of this requires knowing what the thing is. We do all sorts of talking about things without knowing what they are, that's how we learn. If we had to know everything before we could say anything, how could one every get to that state of being able to say anything?

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Quoting Metaphysician Undercover

It's inadequate as a representation of what is actually going on.

It's not a "representation of what's going on". It's a measurement of its position at two points in time, and a calculation of it's average velocity between those two points in time. Of course it's inadequate for a job it's not meant for, and a job it's not doing. You're inadequate for swimming deep underwater without equipment for hours at a time. Everything is inadequate for something, that goes without saying.

Quoting Metaphysician Undercover

How do you think that a determination of an average speed is at all useful toward representing acceleration?

If you determine an average speed around one second and an average speed around another second, you can ascertain how much it accelerated or decelerated between those seconds, which is what I did.

If at second one it was going X m/s, on average given the surrounding .2s, and at second two it was going Y m/s, on average given the surrounding .2s, then between 1s and 2s it must have accelerated or decelerated a certain amount. And we could even verify that by looking at some .2s intervals between 1s and 2s. We have the data from the high speed camera, we can just look you know. 1.1s - 1.3s, what was the average velocity? 1.3-1.5, 1.5-1.7, 1.7-1.9. We can just do the same process and look.

You're trying to go too fast. You can go slow. We have the data from a high speed camera, we can take our time analysing it. You don't need to have a "perfect representation of everything immediately", which is what you seem to want. Just take it slow.

I took it slow and just built up a couple facts. Those couple facts were, around the 1s mark it was going about 9.8m/s, around the 2s mark it was going about 19.6m/s, etc. I'm not building a perfect representation here, I'm just looking at some facts.

Quoting flannel jesus

It's a measurement of its position at two points in time, and a calculation of it's average velocity between those two points in time. Of course it's inadequate for a job it's not meant for, and a job it's not doing.

A calculation of average velocity is inadequate for producing a measurement of acceleration, and this is the "job" we are discussing and "the job it is meant for" in your example. Do you not agree?

Quoting flannel jesus

If you determine an average speed around one second and an average speed around another second, you can ascertain how much it accelerated or decelerated between those seconds, which is what I did.

That requires the assumption of "constant" acceleration which is a careless logical flaw, in your own words. And in reality, in real physical circumstances the evidence shows that acceleration is never constant in that way because of conflicting forces, like air resistance. The claim that acceleration in a vacuum is constant is completely unproven because of this faulty way of calculating it, which already assumes that it is (begs the question).

Quoting flannel jesus

If at second one it was going X m/s, on average given the surrounding .2s, and at second two it was going Y m/s, on average given the surrounding .2s, then between 1s and 2s it must have accelerated or decelerated a certain amount. And we could even verify that by looking at some .2s intervals between 1s and 2s. We have the data from the high speed camera, we can just look you know. 1.1s - 1.3s, what was the average velocity? 1.3-1.5, 1.5-1.7, 1.7-1.9. We can just do the same process and look.

Now you are taking a number of averages, each one having the problem I described, and making a further average, so you now amplify the problem

I agree that for many practical purposes the use of averages is completely acceptable. But this is not what we are discussing. We are discussing whether this use of averages provides a truthful representation, and if not, then what problems arise from trying to use it where it is inadequate.

So, the high speed cameral has limitations, and when we get to situations with things accelerating at an extremely rapid rate, in an extremely short period of time, as in the case of high energy physics, the high speed camera is inadequate. And, the fact that the assumption of "constant acceleration" is adequate and useful at low rates of acceleration where a small error is insignificant, is not proof that it would be adequate for high rates of acceleration where the small error would be greatly amplified.

Quoting flannel jesus

You're trying to go too fast. You can go slow. We have the data from a high speed camera, we can take our time analysing it. You don't need to have a "perfect representation of everything immediately", which is what you seem to want. Just take it slow.

Listen jesus, I am a natural living body, and I accelerate in an extremely unpredictable way. That's a feature of living bodies. Now, you can tell me to slow down, take it slow, but if I'm already accelerated, then it too late to prevent that acceleration which has already occurred.

This is very indicative of your attitude toward the problem of acceleration. You seem to believe that we can take measurements of the body in motion, and make averages of that motion, and say that this constitutes a measurement of the cause of that motion (acceleration). But the acceleration itself, which is the cause of the body's motion has already occurred by the time the body is moving.

So you refuse to even get close to the problem I originally brought up. The highest rate of acceleration occurs at the point in time when the body changes from being at rest to being in motion, the point when it starts to move. Do you agree, that this point in time, when motion starts, marks the highest rate of acceleration? But you cannot show this with your averaging method.

Quoting flannel jesus

I took it slow and just built up a couple facts.

Your supposed "facts" are averages, and averages are a form of estimation, which is inadequate for a rigorous, accurate, or precise measurement. So when you assume that an average is a fact, you need to account for the fact of what an average is. An average is a generalization produced from a number of instances of occurrence, which does not say anything true about any particular instance. "Truth" concerning generalizations is categorically different from "truth" concerning particular things or events.

Quoting Metaphysician Undercover

That requires the assumption of "constant" acceleration

Says who? I didn't say that. This isn't careless from me, this is careless from you.

So far in my analysis, I've just looked at a couple slices in time and calculated the average velocity for that slice. We don't have to jump ahead, we have some average velocities. We can look at them, make some intuitive ideas about what they might mean and then look at more data and see if our intuitions continue to hold. That's a pretty natural progression. We don't have to jump to conclusions, we can instead jump to intuitions and then question our intuitions by looking at more data.

It seems like you have a philosophical problem with measuring things and coming to any conclusion at all based on those measurements. That's not a problem for me. Perhaps this is why science doesn't speak to you, and you don't speak to science.

Science is a little messy. Measurements are a little messy. I don't have a problem with that. That's just the reality we have to deal with. If you struggle with that, perhaps that's why your idea of physics is centuries behind everyone else.

Quoting Metaphysician Undercover

Sure, if that's what's there on the screen, then I agree, that's a true representation. The issue is one of interpretation though. Your claim was that this readout means that according to the speedometer the car is going 60mph. But that is not what that readout actually means, it's a faulty interpretation of what the readout means.

Agree that my speedometer could be broken and be a faulty representation. But now my car has 10 million speedometers (it's a very large car) and they all show 60 mph. Is it possible that all 10 million are broken? Well you can't rule it out, but it is reasonable to say that all 10 million can't be broken in exactly the same way.

So is it possible that there is a design flaw in the speedometers and the value is wrong? Well duh, of course it's possible. However I can look out the window of my large car (my car has windows) and I can verify using my eyes that indeed the car is moving. And I open a window and use my handheld velocity checker to verify the 60 mph. I can stick my hand outside the window and feel the wind. I can temporarily unbuckle my seat belt, stick my head out the window and see the tires moving.

So it is clear that the car is moving. Or is it? Uh-oh, maybe I missed something . . .

Is it possible that the car is standing still and somehow we have arranged it so that it appears that the scenery and the road are moving while the car is standing still? Sitting inside my car I can't rule it out - it's theoretically possible. But there are 10 million people outside the car observing the car move and they are verifying (all using different mechanisms to measure velocity) that my car is going 60 mph.

Is it possible that the outside observers are in fact moving and the car is standing still? They stick their fingers in the air and they feel no movement in the air.

Is it theoretically possible that somehow you have arranged this experiment so that the observers are moving at 60 mph but they do not feel any air moving? Possible, but then when they entered the experimental apparatus they would have felt some acceleration through their inner ears when they started moving (our inner ears can detect acceleration). OK - maybe when the observers entered our experimental apparatus the were standing still and we accelerated up to 60 mph very slowly so the acceleration did not register in their inner ears. Or maybe we secretly drugged them before they entered the experimental apparatus and disabled their inner ears.

So is it possible that those observers are unaware that they are the ones who are moving 60 mph and the car is standing still? We can't logically rule it out (we can always add another absurd hypothetical into the mix).

However, per the CToT there is a true statement here:

"Within the accuracy of our measuring apparatus the car is moving 60 mph relative to it's outside environment".

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Reply to tim wood Fascinating stuff - I don't have the time/energy to fully delve into it.

BTW, here's the link: https://thephilosophyforum.com/discussion/14659/page/p1

[edit]. I also recommend the latest Scientific American special issue "Mind Bending Physics". Good article on Bell (among other things).

Quoting flannel jesus

So far in my analysis, I've just looked at a couple slices in time and calculated the average velocity for that slice.

You are calculating the acceleration. That is the subject being discussed. The average velocity from a slice in time cannot be used in your calculation without the assumption that the acceleration in that slice is constant. Suppose that within that slice of time, the velocity varied greatly, perhaps even up and down. Then your average is completely useless as an indication of the real acceleration which is occurring. Therefore the technique is unreliable from the outset. It is only useful under the assumption of constancy.

You are the one going to fast, trying to sneak past the problem with using averages. There is no need to go any further than this, you need to look at the problem of averaging, and accept it. As you yourself explicitly stated, we cannot assume that the motion represented by the average is in any sense constant. That would be a serious logical flaw. Therefore any further extrapolations will not be able to prove anything about the acceleration within any of those slices in time, because it will be hidden by the averaging process. Do you agree with this?

So, do you agree that it is very possible that the rate of change to the speed of the thing (acceleration/deceleration) is extremely unstable within the small parts of those "slices in time"? Furthermore, since any such averaging requires a duration in time, and any duration can be broken down into shorter time periods, this problem inheres within the nature of that technique. The problem is intrinsic to the technique and is unavoidable. So it is impossible that the technique can give us a reliable representation of acceleration. And in our world of high energy practices, the most important and significant accelerations occur in very short slices of time, and this is where that technique of averaging becomes extremely inadequate.

Quoting flannel jesus

It seems like you have a philosophical problem with measuring things and coming to any conclusion at all based on those measurements. That's not a problem for me. Perhaps this is why science doesn't speak to you, and you don't speak to science.

Science is a little messy. Measurements are a little messy. I don't have a problem with that. That's just the reality we have to deal with. If you struggle with that, perhaps that's why your idea of physics is centuries behind everyone else.

I work in a field where the better the measurement is, the better the job is. So I've learned that it is always a good idea to keep looking for, and finding, new ways to clean up the bad habits of messy measurements.

Quoting EricH

Well you can't rule it out, but it is reasonable to say that all 10 million can't be broken in exactly the same way.

Unless each speedometer measures the velocity in a different way, it's very likely that they would all be inaccurate in the same way. For instance, if the car had the wrong size tires on. But for the sake of argument, let's say that each speedometer used a different technique to show the speed. Do you agree that if they each worked as intended, it's highly unlikely that they would ever all show the exact same thing, unless perhaps that might occur if the car was parked, and there was no wind, and the earth stopped spinning? !0 million different ways to measure the speed would take some serious innovations.

And I don't see the relevance of your long winded post.

Quoting EricH

However, per the CToT there is a true statement here:

"Within the accuracy of our measuring apparatus the car is moving 60 mph relative to it's outside environment".

I don't see why I'm supposed to agree to this. All measurements are fundamentally subjective, and so measuring apparatuses apply principles which are somewhat arbitrary, therefore statements about "the accuracy of our measuring apparatus" are not truth-apt. As I mentioned already, measurement principles are pragmatic, they are designed for specific purposes. So the accuracy of the measuring apparatus is always suited to the purpose it is designed for, and it is judged by its usefulness not for truth or falsity.

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Reply to Metaphysician Undercover you're asking the right questions, except instead of saying "let's look at the data and check if the acceleration is going up and down wildly" you're just saying "oh well we can't know for sure so I give up, there's nothing left to discover."

Don't give up so quick, we have a lot of data from the camera. I mean, if you WANT to remain ignorant of the pattern of how things fall by gravity, then by all means give up here. But the rest of the world is operating on many centuries worth of physics past the point that you give up.

Quoting Metaphysician Undercover

So the accuracy of the measuring apparatus is always suited to the purpose it is designed for, and it is judged by its usefulness not for truth or falsity.

Precisely. And the purpose of the 10 million different measuring apparatuses (apparati?) is to measure velocity. So QED we are measuring velocity. And so the statement is true per CToT. We are not dealing with your metaphysical notions of truth or falsity here. And of course it is not 10 million. Duh.

Now let's move over to our acceleration issue.

Quoting Metaphysician Undercover

I agree that for many practical purposes the use of averages is completely acceptable.

First of all it is clear that you are OK that we can measure average velocity.

Quoting Metaphysician Undercover

But the acceleration itself, which is the cause of the body's motion has already occurred by the time the body is moving.

Acceleration does not cause anything. No wonder you are confused. Acceleration is a change in the velocity of an object. An object can undergo acceleration by being acted on by a force (F = ma) or by being affected by the curvature of spacetime.

We drop our bowling ball. After one second we determine that the velocity is ~9.8 meters per second (m/s). (I'm using the "~" here to mean average). After two seconds our velocity is ~19.6 m/s. After 3 seconds the velocity of our bowling ball is ~29.4 m/s.

Hmm something is going on here. Let's look more closely - let's chop up time a bit more finely - 10 times per second. After 0.1 seconds our ball is going ~0.98 m/s. After 0.2 seconds it's going ~1.96 m/s, etc. And lo and behold, after one second the velocity is ~9.8 m/s.

No matter how finely we chop up time - or how many different ways we chop up time - we get the same results. So this is a true statement:
The velocity of our object is increasing by 9.8 m/s every second within the limits of accuracy of our measuring devices.
Again, we are using CToT, not your metaphysical notions of truth.

Quoting Metaphysician Undercover

So, the high speed cameral has limitations, and when we get to situations with things accelerating at an extremely rapid rate, in an extremely short period of time, as in the case of high energy physics, the high speed camera is inadequate. And, the fact that the assumption of "constant acceleration" is adequate and useful at low rates of acceleration where a small error is insignificant, is not proof that it would be adequate for high rates of acceleration where the small error would be greatly amplified.

I didn't give this bit the attention it deserves. You said "the fact that the assumption of "constant acceleration" is adequate and useful at low rates of acceleration" - that's wonderful! If you agree that it's useful and adequate enough at low rates of acceleration, then you've accepted the only thing I really wanted you to. Gravity accelerates things at 9m/s/s, on planet earth, at least for the low rates of acceleration that we measured.

You go on to talk about other instances of acceleration that aren't directly caused by gravity, which I think it's fair to say is beside the point. The conversation is about how gravity accelerates things, not about how your leg muscles accelerate your own body.

You and I both agree, 9.8m/s/s is an adequate and useful idea of how gravity accelerates objects, on earth and for low speeds. And in fact Newtonian physics, which has pretty much the same simplistic vision of gravity as that, was enough to get human beings on the moon! How wonderful.

9.8 m/s/s isn't some perfect magical truth. It's an approximation that works, that we derived by simply looking at the world and taking notes. If you agree that it's useful and accurate in the contexts we generally use it, then you agree with me.

Woops, mispost

Quoting tim wood

I was not any good at calculus, but I think calculus is what you are talking about. So question to you, MU: do you buy calculus? Or is that flawed and misleading?

As I said, I think calculus is very useful in very many situations. However, its usefulness has limitations. and when it is employed beyond these limitations it is misleading. This I believe is the case in modern high energy physics, it is employed beyond its limits. And, I believe It is misleading because people like you will argue that the problem which has not been resolved, the problem I referred to in the exchanges between Newton, Leibniz, and Berkeley, has actually been resolved.

This is why calculus is misleading, it has produced a very acceptable work-around for the problems first exposed as Zeno's paradoxes, which is very useful in a wide range of practises. However, since it does not actually resolve the problems of Zeno's paradoxes, these problems reappear, as the uncertainty principle for example, when we reach the limits of its applicability. If one insists that the problems have been resolved, then the true nature of the uncertainty principle will not be understood.

Quoting flannel jesus

you're asking the right questions, except instead of saying "let's look at the data and check if the acceleration is going up and down wildly" you're just saying "oh well we can't know for sure so I give up, there's nothing left to discover."

Don't give up so quick, we have a lot of data from the camera. I mean, if you WANT to remain ignorant of the pattern of how things fall by gravity, then by all means give up here. But the rest of the world is operating on many centuries worth of physics past the point that you give up.

I'm not ready to give up. However, I'm already fully aware of the process you are laying out, and completely understand and respect its usefulness. Therefore I am bored and ready to move on. I can tell you however, that there is a point in time when we can know for sure that the acceleration is going up wildly, and that is at the 'zero point' in time, when motion starts.

So I will ask you now, are you fully aware and respectful of the problem that I am talking about? If so, then lets move directly to that specific problem and address it directly. In your example, there is a 'zero point' in time, the time when motion is supposed to have begun. So let's bring this zero point into your numerical expressions, and produce a "slice in time" which is the period between -.1s and +.1s. Do you agree that the averaging technique will not give a good representation of this time period? If you agree, then how do you propose that we deal with this period of time?

Quoting flannel jesus

I didn't give this bit the attention it deserves. You said "the fact that the assumption of "constant acceleration" is adequate and useful at low rates of acceleration" - that's wonderful! If you agree that it's useful and adequate enough at low rates of acceleration, then you've accepted the only thing I really wanted you to. Gravity accelerates things at 9m/s/s, on planet earth, at least for the low rates of acceleration that we measured.

The problem though is that we have no way to measure the rate of gravitational acceleration at the precise moment that a thing starts to fall, and it actually may be completely different from your calculated rate.

Quoting flannel jesus

You go on to talk about other instances of acceleration that aren't directly caused by gravity, which I think it's fair to say is beside the point. The conversation is about how gravity accelerates things, not about how your leg muscles accelerate your own body.

No, I started the conversation, as a discussion about the problem of measuring acceleration in general, that's why I referred a number of times to the effects of this problem on quantum mechanics, as the uncertainty principle. It was Eric I believe, who started talking about gravity as a specific example of acceleration, and then you. But that was brought up as an example of acceleration. It appears like you just do not want to look at the problem I mentioned.

Quoting EricH

Precisely. And the purpose of the 10 million different measuring apparatuses (apparati?) is to measure velocity. So QED we are measuring velocity. And so the statement is true per CToT. We are not dealing with your metaphysical notions of truth or falsity here. And of course it is not 10 million. Duh.

My spell check did not like "apparati". Anyway, I apprehend a slight mistake here. "The purpose of the measuring apparatus is to measure velocity" is true by coherency theory of truth, not by CToT. This is the categorical separation I referred to, and to mix them up is known as a category mistake. To state the "purpose of x is..." is to make a statement which is true or false by a stated definition, not by correspondence.

Quoting EricH

Acceleration does not cause anything. No wonder you are confused. Acceleration is a change in the velocity of an object. An object can undergo acceleration by being acted on by a force (F = ma) or by being affected by the curvature of spacetime.

I might agree to this, but you are just drawing us further away from the possibility of any truth by CToT. If acceleration is not considered to be the cause of change in velocity, being the intermediary between the prior motion and the posterior motion, and instead is just a calculated change in motion, then there is nothing real in the world which "acceleration" refers to. We can see the same issue with "energy", we can say that the word refers to something real in the world, or we can say that it's just something calculated according to a formula. You seem to be choosing the latter, which denies the possibility of correspondence truth in this subject.

Quoting EricH

No matter how finely we chop up time - or how many different ways we chop up time - we get the same results. So this is a true statement:
The velocity of our object is increasing by 9.8 m/s every second within the limits of accuracy of our measuring devices.
Again, we are using CToT, not your metaphysical notions of truth.

This is not truth by correspondence theory, it is true by coherence theory. The velocity determined is correct by the method of calculation, but this does not necessarily correspond to anything real.

Quoting Metaphysician Undercover

So let's bring this zero point into your numerical expressions, and produce a "slice in time" which is the period between -.1s and +.1s. Do you agree that the averaging technique will not give a good representation of this time period? If you agree, then how do you propose that we deal with this period of time?

Why would it fail to give a good representation? The only problem with our high speed camera data for this moment in time is that it has limited resolution, so we wouldn't necessarily be able to see how it starts moving at that moment in time (I've been rounding previous measurements of distance to 2 decimal places to sort of mimick the problem of camera resolution).

We'd have to film it up close and make sure everything is much more precise at the moment the thing is dropped. But there's no problem with it conceptually. First we get the average velocity between -.1s and .1s, and then we can look at how that velocity changed over that time frame by dividing that into even smaller segments, and then even smaller ones if we still have more questions.

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Quoting flannel jesus

Why would it fail to give a good representation? The only problem with our high speed camera data for this moment in time is that it has limited resolution, so we wouldn't necessarily be able to see how it starts moving at that moment in time (I've been rounding previous measurements of distance to 2 decimal places to sort of mimick the problem of camera resolution).

The camera takes two shots, one at -.1s, and one at +.1 seconds. You produce the average, the speed for that time period, but this is obviously not a good representation. In reality the thing is moving in half that time period, and not moving in the other half. Furthermore, in the half that it is moving, it's average speed must be twice as fast as what your average says for that time period. I think that's a very significant, and in some applications, potentially a very important difference. If we add to this, the fact that by the special theory of relativity simultaneity is relative, there is the potential for even more significant inaccuracy, and uncertainty.

Quoting tim wood

Is calculus used to solve problems?

Yes

Quoting tim wood

And just what are the problems of Zeno's paradoxes?

Try Wikipedia.

Quoting tim wood

Achilleus gets where he's going, and faster than the tortoise. The arrow flies through the air and so forth.

Not according to the logic applied to the premises. That's why the term "paradox" is used.

Quoting tim wood

As to the arguments themselves. they all involve some faulty assumption.

Yes, they are faulty assumptions about the continuity of space and time, which are still held. You are on the right track here. Do you see that these same faulty assumptions are still held today? Next, can you apprehend that improved mathematical axioms will not resolve the the problems created by these faulty assumptions. No matter how good the logic, false premises will always leave the conclusions unsound.

So the issue is that space and time are understood as infinitely divisible continuums, or one continuum, and so division of them, or it, may be completely arbitrary. This does not correspond with reality, hence Zeno's paradoxes. The proposed solution was "infinitesimals", but these were arbitrary, and therefore still not consistent with reality. Calculus bring "infinite" right into the mathematics, and this is a form of indefiniteness, hence uncertainty.

Quoting Metaphysician Undercover

You produce the average, the speed for that time period, but this is obviously not a good representation.

A good representation of what? You keep saying things like "inadequate" or "not a good representation". Some measurements are adequate for some purposes and inadequate for other purposes. You can't just raw say it's inadequate, it can only be inadequate in relation to some goal.

Now it's not like you gave me a specific goal and I said "all we need to do is measure the location at these points in time". In fact measuring them at those points in time was YOUR suggestion, not mine. Don't tell me it's inadequate - tell yourself. If you want me to help you get adequate measurements to accomplish some goal, then all you have to do is tell me the goal and ask.

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Quoting flannel jesus

A good representation of what? You keep saying things like "inadequate" or "not a good representation". Some measurements are adequate for some purposes and inadequate for other purposes. You can't just raw say it's inadequate, it can only be inadequate in relation to some goal.

I mean "a good representation" of what actually happened, as i said, the goal is truth, in the sense of correspondence.

Quoting flannel jesus

Now it's not like you gave me a specific goal and I said "all we need to do is measure the location at these points in time".

I gave the goal, truth. That's why Eric got sidetracked and started talking about correspondence theory of truth.

Quoting flannel jesus

In fact measuring them at those points in time was YOUR suggestion, not mine. Don't tell me it's inadequate - tell yourself.

No, I'm telling you it's inadequate. I specifically requested those points in time to demonstrate to you, the inadequacy of your technique. Of course you would not suggest those points, because that time period, the time when acceleration starts, cannot be adequately represented by your technique. And this is a very real problem for high energy physics. I'm starting to think, that just like I was fully acquainted with your measuring technique, of using averages, you were actually fully aware of the problem I am talking about. And, like tim, you simply want to ignore it, and deny that it is a problem.

So now you intentionally avoid that specified time period saying, 'that's not my problem, it's your problem, because I have no interest in that time period. My averaging method serves my purpose, and I do not care if it doesn't serve yours. So keep your problem to yourself, and don't try to make your problem my problem.' But I'm not saying it's your problem or mine, I'm saying it's a problem with the technique. It's the technique's problem.

Quoting tim wood

Infinite divisibility a convenient fiction in calculus...

I see, I need to say no more on this issue, you've stated my case for me.

Quoting tim wood

He supposes (reasonably for him we may suppose) there is an interval of time so short that within it the arrow is not moving.

This is a misrepresentation. He is not talking about a short interval of time, he is talking about a point in time. I mean, you can say that you do not believe that there is such a thing as points in time, therefore this assumption is wrong, but the problem is that we always use, and refer to, points in time when making any temporal measurements, as the start and end points of the measured period. The start point divides time into prior and posterior, such that there is no duration within that point.

Quoting tim wood

And so far I do not think I have written anything you do not know perfectly well, or disagree with.

As stated I disagree with your representation of Zeno's arrow paradox. He is very clearly talking about points in time, not infinitesimal intervals of time. And, your statement, that there is no such thing as a point in time, does not negate the fact that we use points in time for all of our measurements of time. So, you might insist that points in time are not real, they are "a convenient fiction", but as the premise for temporal measurements, you are then insisting that all temporal measurements are unsound conclusions.

Suppose objects are moving relative to each other. And, we can describe the spatial relations between objects. Would you not agree that any specific spatial relations would only exist at "a point" in time? The objects are moving, so any interval of time would not provide determinate relations. So the reason for the assumption of points in time is to provide for "truth" in spatial relations of moving objects. Without these points there is no such truth. Now, not only are temporal measurements unsound, but spatial measurements as well.

Quoting tim wood

But that aided by keeping in mind that all the rules, laws, theories, and mathematics just attempts at representations of the world itself (-as-it-is-in-itself) expressed in terms of what people can understand.

OK, so if you believe that mathematics attempts at representations of the world, and you also apprehend that calculus is based in "a convenient fiction, then it ought to be a no-brainer for you to see the deficiencies of calculus which I am pointing to. Simply put, it fails to do what mathematics "attempts" to do, in your words, give us a representation of the world. It just gives us a convenient fiction.

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Quoting Metaphysician Undercover

No, I'm telling you it's inadequate. I specifically requested those points in time to demonstrate to you, the inadequacy of your technique.

Quoting Metaphysician Undercover

So now you intentionally avoid that specified time period saying, 'that's not my problem, it's your problem, because I have no interest in that time period.

Ok so you realise it was your idea to do that, so let me just reiterate how inappropriate is for you to complain to me about how bad your idea was.

If you ask me to figure out a way to get an answer, I can tell you, and THEN we can go into if the technique is adequate or not. Until then, your own problem with your own technique is something for you to work on with yourself, and it's not a criticism of me or any idea I've had.

I'm completely happy to look at that time period too, you just never asked me a question about it. Instead of asking, you started telling me what I would do. You're doing things in the wrong order and being too hasty, making careless assumptions again. Slow down.

Quoting tim wood

I myself would say that of such things, exact measurement is impossible in principle and thus we do the best we can, which is usually pretty well, and this not a failure or a deficiency, but instead a success.

:100: +/-0.000000001

Quoting tim wood

And you and I, and I suspect you and most people, attach an altogether different significance to what you call the "deficiencies." And yes, people often ignorantly refer to "points" in time. But calculus usually refers to the value of a variable as some input approaches a limit - no infinities, although they're approached, and no "points in time." And if Zeno wants to think in terms of points in time, what is that to us beyond an historical oddity - however reasonable it may have seemed to him at the time? And to be sure, "point in time" is easy to say, but were there actually such a thing, a durationless interval, then atomic motion would stop and everything on the instant collapse.

Sure, call it a "limit" instead of a point if you want, that doesn't change what it refers to, and that is a point of division, which separates one period of time from another. And as I said, the problem is not specifically that such limits or points are unreal, the problem is that the concept is applied as if they are real. So you can argue all you want, that there is no real problem because we all know that such limits are not real, but then the problem is the hypocrisy with which the concept is applied, as if the limit is real.

Quoting tim wood

I think we're at an impasse. i think you hold that nothing can be measured exactly, of things subject to measurement, and thus all knowledge of such things is deficient and flawed. I

No, this is not what I'm arguing. I am pointing out the flaws and deficiencies and indicating that I believe a better system is possible. Whether or not exact measurement is possible is completely irrelevant, What is relevant is whether it is possible to improve the current technique. So, unless you can demonstrate that it is impossible to find a better system than the use of limits, then my activity of pointing to the flaws in this system and suggesting that we find a way to change this system, is very reasonable activity. Don't you agree, that pointing to the flaws and deficiencies of a technique, and indicating that these ought to be rectified, is a very good thing to do, even if those who currently use the technique tend to feel insult, offence, and so they strongly defend the technique which they use?

Quoting flannel jesus

If you ask me to figure out a way to get an answer, I can tell you, and THEN we can go into if the technique is adequate or not. Until then, your own problem with your own technique is something for you to work on with yourself, and it's not a criticism of me or any idea I've had.

I am not criticizing you, or any idea you've had, I am criticizing the technique you are demonstrating. I am explaining that your technique for modeling acceleration through the application of averages, is inadequate for representing the most significant and important aspect of the concept of "acceleration", and this is the point in time at which acceleration begins.

Now it seems to me that we disagree as to whether this truly is the most significant and important aspect of "acceleration". Your model places this point as outside the representation, a limit which is approached, as tim states above. So you are inclined to say it's not my problem, that point in time is outside of "acceleration" as I model acceleration. It's not a part of "acceleration" so your criticism is irrelevant. I insist that it is an integral part of your model of "acceleration", significant, important, and necessary to your representation, so this is a requirement. The application of the limit is the primary premise.

Quoting flannel jesus

I'm completely happy to look at that time period too, you just never asked me a question about it. Instead of asking, you started telling me what I would do. You're doing things in the wrong order and being too hasty, making careless assumptions again. Slow down.

Well, if you had been more attentive to what I wrote, you would have seen that this is the question I was asking about, when the mention of "acceleration" first came up, and we could have gotten right to the problem, without us wasting each other's time for the last nine days or so.

I see now, that my posts were addressed to EricH, as Eric is the one who brought up acceleration in the midst of our discussion concerning the possibility of medium-free waves. Perhaps you missed those posts, so I'll reproduce them now.

Quoting Metaphysician Undercover

That something is "accelerating" requires a multitude of measurements of velocity, and each measurement of velocity requires multiple determinations of spatial-temporal location.

Quoting Metaphysician Undercover

The concept of "acceleration" involves a fundamental philosophical problem. Acceleration is the rate of increase of velocity. So if an object goes from being at rest, to moving, there is a brief period of time where its "acceleration" is necessarily infinite. This is a fundamental measurement problem, and another form of the same problem is at the heart of the uncertainty principle of quantum physics, as the uncertainty relation between time and energy in the Fourier transform.

This problem was exposed by Aristotle as the incompatibility between the concept of "being" (static) and the concept of "becoming" (active). The way that modern physics deals with this problem, through the application of calculus does not resolve the problem. It simply veils the problem by allowing the unintelligible issue, infinity, to be present within the mathematical representation.

Now, the very same philosophical problem which Newton and his contemporaries had to deal with in the relationship between bodies, becomes paramount in modern physics in its relationships of energy. The issue though, is that Newton and his contemporaries were dealing with relatively long durations of time, so the methods of calculus were adequate for covering up this problem which only increases as the period of time is shortened. Now physicists are dealing with extremely short durations of time, so the uncertainty becomes very relevant and significant. That's what the time/energy uncertainty indicates, the shorter the time period, the more uncertain any determination of energy will be.

Accordingly, using the current mathematical conventions, such calculations of acceleration will never be done "beyond all reasonable doubt", because the current convention is to allow the unintelligible (infinite) to be a part of the mathematical representation..

You see, I have always been asking about that time period, and the whole interim has simply been a diversion. Do you see why it appears to me like you are simply avoiding the issue? You say "slow down", but we are discussing the opposite, acceleration. So unless you can show how your actions of attempting to decelerate the discussion are relevant, then I can only see your digressions as intentional diversions.

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Quoting tim wood

And at the risk of trying your patience, what exactly are those flaws and deficiencies which justify your calling the "system" hypocritical? The reason I ask is that in sum you appear to be criticizing a tool, a tool which given appropriate inputs delivers results to an arbitrary degree of precision.

The flaws I spent the last week and a half explaining. And it isn't the system, which I say is hypocritical, but it's people like you who recognize the faulty assumptions (arbitrary points in time for example) inherent within the system, then insist that there are no deficiencies to the system, who I say are hypocritical.

Quoting tim wood

Seen the correct way, calculus, e.g., is neither flawed nor deficient, and certainly in no way hypocritical. Instead it is exact. In a sense then it is either all right or all wrong, and because all that it does is just what it does, then it must be all right. Further, since it gives answers to an arbitrary degree of precision, it is therefore in itself altogether correct.

This is very unsound logic. A system which uses numerous different axioms must be either all right or all wrong? That doesn't even make sense. And you say "it is exact", but also to "an arbitrary degree of precision". Making exactness arbitrary leaves "exact" as completely meaningless. So you are saying absolutely nothing here. And your "metaphor" is even worse, being in no apparent way, analogous.

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Quoting tim wood

By that I meant that calculus is exact in what it does. Same formulas same inputs yield the same answers.

Right, 2+2 always equals 4. There's is no doubt about that. But how this relates to the physical world is another issue altogether. I'm interested in the latter, not the former, because the former is very boring to me. And your suggestion, "it works", is equally boring.

Quoting tim wood

And yes, people often ignorantly refer to "points" in time. But calculus usually refers to the value of a variable as some input approaches a limit - no infinities, although they're approached, and no "points in time".

Don't be so critical. I've used "points in time" frequently in complex dynamical systems. And in complex analysis, a contour in the complex plane, z(t)=x(t)+iy(t), has a value for t=.5, e.g. And you think physicists don't use points? Do you think that limits define points, or points define limits? As for the infinite, there is indeed a "point at infinity" in complex variable theory.

Quoting Metaphysician Undercover

So, unless you can demonstrate that it is impossible to find a better system than the use of limits, then my activity of pointing to the flaws in this system and suggesting that we find a way to change this system, is very reasonable activity

This might have made a semblance of sense had you been present when my math genealogical ancestor, Karl Weierstrass, and Cauchy were pulling together the common definition of limit two hundred years ago. You could have presented them with your clearly defined objections to their work and been present for their reactions. Oh, to have been a fly on the wall. :cool:

Reply to tim wood The notion of "points in time" is rarely debated in science and math to the best of my knowledge. Do dimensionless points exist? This is more a philosophical issue than a mathematical one. Does a point on a ruler really exist? It certainly corresponds to a real number, but there are those who question the existence of irrationals. So, what happens to that point? It exists for some but does not for others?

Calculus is fundamental to the major branch of mathematics called analysis, founded on the idea of limits. Ordinarily, it assumes the existence of these points regardless of whether one speaks of rulers or time scales. Real analysis, the underlying structure of calculus, contains the axiom of completeness, which means points exist as viable entities. But some would say temporal points are different.

I thought of the famous debate between Einstein and the popular philosopher, Bergson, a hundred years ago. However, their issues revolved about whether time itself was independent of human experience. I'm not sure instants in time came up. But more recently a non-academic wrote a paper on time and physics in which he argues against any sort of "instant" in time. Some thought him brilliant, but others thought him a conveyor of nonsense. The latter is the more popular among physicists.

The point at infinity in complex analysis is the north pole of the Riemann sphere. No matter where you go in the plane as you move out away from the zero point the projection onto the sphere moves toward its north pole. So, in this sense, there really is a "point at infinity". :cool:

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Quoting tim wood

?jgill
Would you agree with me that "point in time" is at best a locution to convey informally in language an aspect of a technique useful in math, and not otherwise real?

Would you say an interval of time is real? Consider the intervals [0,1] or (0,1). Each requires end points, one includes its end points and the other does not. What are these points? Fictions designed for the sake of argument? This makes intervals of time as suspect as their end points.

Bergson compared the unfolding of time as a tape steadily rolling off one drum and onto the other. So the word "duration" implies an infinite interval. Thus any notion of time's flow excludes finite intervals. The exact duration of an event is as much a non-real artifice as a point in time.

A photo of Zeno's arrow, frozen in flight, implies that relying on a dimensionless point excludes the recognition of the arrow's momentum. So, yes, points in space and in time's continuum are mostly mathematical objects. I say mostly since I consider them to be metaphysical "objects", outside the realm of physics - which is what many physicists concluded after reading Lynds' paper on the non-existence of points in time. Neither provable or excludable. Just fodder for endless, non-productive philosophical discussions.

Incidentally, the appearance of Lynds' article (2003) sealed the fate of Foundations of Physics Letters, which ceased publication after 2006. :cool:

Reply to jgill The problem with the declaration that points in time are unreal is that the photoelectric effect demonstrates that there must be very real points in time. The way that electrons react to electromagnetic radiation indicates that there must be a point in time when an electron is emitted. The emission occurs as a "quantum" of energy at a determinate point in time, rather than as a continuous flow of energy.

The fact that we have not been able to understand or properly identify these real points in time manifests as the misunderstanding of the wave function collapse. The collapse must be in some sense real because it is observable, but since the conventional employment of points in time is done through arbitrariness rather than correspondence, as points are apprehended as unreal, the result is many worlds, according to many possible points. On the other hand, complete denial of the reality of points in time produces a continuous wave function with no possibility for any real points of collapse.

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Quoting tim wood

Consider the intervals [0,1] or (0,1). Each requires end points, one includes its end points and the other does not. — jgill

Kindly correct me as needed, but I'm thinking both include their endpoints; in the one case the endpoints are known and identified, and in the other, unknown and unidentifiable. But whatever the status of their endpoints, both intervals.

[0,1]={t:0<=t<=1} and (0,1)={t:0
Quoting tim wood

And finally, just for the heck of it, what is a "metaphysical object"? And what exactly is "the wave function collapse"? As an informal descriptive term, I (think I) get it. But if it's more than that, if it's a something, then what is it?

A dimensionless point, not a pencil dot on a map. Or an infinitesimal in non-standard analysis. An object of the mind, not something that has a physical presence. IMO.

"the wave function collapse": Differential equations can have more than one solution, and a linear equation thus has all linear combinations of these solutions. Upon measurement, one discovers which of these is correct. For example, dy/dt=1 implies y=t+c, c is an arbitrary constant. Upon measurement I find that c=-.5, e.g. But this is overly simplistic and there does appear to be some weird stuff going on. In my opinion the wave function is not ontological. In fact, the Schrödinger equation in its simplest form is
dy/dt=Ky

Quoting tim wood

As I read these, there's a failure to distinguish between what we might call a map co-ordinate and a dimension/duration.

The problem is that there is no specific real thing, in physics, which corresponds with "duration". Duration is simply a relation between one activity and another, and as a relation it is a feature of the coordinate system employed. That is why there is serious ontological discussion as to whether time is real or not, and the general consensus is that the principles employed in physics assume that time is not real.
[quote=Wikipedia]In physics, time is defined by its measurement: time is what a clock reads.[/quote]

Notice, a clock does not read time, people read time with the use of a clock. So it's just like any other measurement. If I measure between the house and the car, the reading, 50 meters for example, is part of the map. Likewise with time and also "duration". In physics duration is part of the map, as a measurement.

Since the measurement of time is just a number of 'units' produced by relating one activity to another, physicists have no idea of what is actually being measured. The 'units' are completely artificial. The tendency is to claim that there is nothing real, and time is an illusion. This effectively avoids the issue. But any physicist (more correctly metaphysician), who wants to understand the reality of what is being measured, is confronted with the question of what constitutes a real unit of time.

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Quoting tim wood

Sure there is, it's called time. If you'll read your own post, your comments are on the measurement of time, not time itself.

The point though, in physics, time is defined as the measurement, as the Wikipedia quote indicates. There is no "time itself" in physics, because "the measurement" is simply a product of the application principles. Therefore time is part of the map, not the territory, just like space.

This is the same issue which we discussed with the aether earlier. Without the medium, (the substance within which the waves exist), "space" is just a feature of the measurement system, the map. This means that what is referred to by terms like "space-time", as well as "the wave function", are features of the map's measurement principles or rules, with conventions for application in physics. but without any corresponding reality in the physical universe.

Think of the way that a coordinate system is a feature of the map, a product of the measurement principles. There are conventions for application in various situations, the proper technique for applying a coordinate system in practise, but there is no part of the physical universe which corresponds with the coordinate system. That is the reality of both "space" and "time". in the practise of physics, they are a system of measurement principles, application techniques, with nothing in the physical universe which corresponds.

Nothing’s the Matter With Antimatter

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Quoting tim wood

Seems pretty real to me when I have to go anywhere. And if it is just a feature of the measurement system, then what is he measurement system measuring?

When you go places, do you think you move through space? You are actually moving through air, i think.

We measure different aspects of the world, the size of things, the distance between things, etc.. We do not measure space. The same is the case with time, but it is a more complex measurement involving a comparison of activities. There are conventions for such comparisons, and when we employ them, we get a determination of a duration of time.

Quoting tim wood

Really? No part that corresponds? Then what is the coordinate system coordinating?

A radical idea! You could try making sense! You could start with your claims as I've listed in this post! That is, no time, no space, no physical universe. Don't worry, I'll breathe.

I don't think it's a "radical idea", I think it's common understanding. So, I'll start with the statement above, and if you cannot grasp this, there's probably not much point to proceeding in this discussion.

Here's an example Reply to tim wood which might serve to facilitate discussion. Suppose I draw a sketch of the horizon from my perspective, and I mark on it various static objects of the landscape like hills, trees and buildings. All of those objects have something real in the world, independent of my sketch, which are referred to, and the sketch is a sort of map. Then I add a spot, a mark on the map, and designate it as the place where the sun comes up. Notice, that this mark does not refer to any real, independent object whatsoever, it refers to a place, a location. In what way would you agree, or disagree, that there is nothing real in the physical world which this mark on the map refers to?

Can we not regard our experiences of 'the real world' as something which is being filtered through our sensory system, which can be likened to a kind of 'headset', analogous to wearing a VR headset, and that what is truly going on 'behind the scenes' is far too complicated for us to understand? However we want to define the physical world, in the final analysis, it has come to represent something our evolutionary pass has equipped us to survive in. Logic, in this context, is just the label we assign to events and experiences that retain a consistent pattern over time and serves the needs of our survival and well-being.That's why, I think, when the quantum world was discovered, it was such a shock to many because it does not seem to fit our patterns of nature, which we are a part of.

Reply to Richard Townsend

:100:

wonderer1, exactly, so what we term 'reality' may only really be our subjective reality and bear no resemblance to the truth. What is the term? 'You can't handle the truth?' So, if there is no absolute reality, this may be why we get surprised when we delve into new areas of physics, such as the quantum world, where there have never been any preexisting 'rules of engagement' so to speak, and so it is how we set-up an experiment in order to gain new knowledge that sculptures this new landscape. My take on it is we can never totally divorce ourselves from any experiment, which means we are really performing an experiment not only what we think is the objective world, but on the system as a whole, including ourselves! For example, how else may entanglement be explained within our current framework of spacetime? It can't, which seems to indicate that spacetime and entanglement are merely human constructs that account for data collection. Presumably, this is how scientific progress proceeds - by observation of data and modification of existing scientific theories. This is what happened to Newtonian mechanics,which was a perfectly good description of the cosmos up to a point, but because it was incomplete, required a radical new approach, i.e.The Theory of Relativity! The data required it. I think people should remember that whatever scientific instruments are used in any measurement, the human 'biological measuring instrument' plays a crucial part since it forms part of a causal chain which yields the final result.

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tim wood, the problem is, any 'proof' will simply mean proof of what we have observed, ergo, a subjective kind of proof. One cannot step out of one's consciousness and observe in any independent sense. A radio cannot be a TV, although it does have the capacity to receive and convert sound waves, but not pictures. Similarly we cannot know anything outside of our consciousness although we do have the ability to receive things analogous to 'sounds waves', so to speak. This is a a priory kind of proof, not a scientific one. That is impossible.

Quoting tim wood

Are you suggesting that movement absent air is not possible?

No, I'm saying that movement through "space" (see below for definition) is not reality. Real movement, in the real physical world. is always through a medium, air, water, etc.; it is not through "space" unless space is conceived of as a real a medium, like the aether, which it is not in conventional physics.

Quoting tim wood

Time for you to define "space" and "time." If we only measure distance, what does distance refer to?

OK, let's start with "space", as I already provided a sort of definition of "time" in physics, from Wikipedia, but you either did not understand it, or disagreed with it (I haven't figured out which yet).

So, from my OED, the first definition of "space" reads like this: "a continuous unlimited area or expanse which may or may not contain objects etc.".

What I've been telling you, is that this does not refer to anything real, independent, in the world. It is an ideal which facilitates all sorts of human activities of conceptualizing, measuring, etc.. Take your example of movement now. Space is a concept which can be applied to help us model movement. However, if we produce a representation of an object moving through space, this is not a real (true) representation, because empirical evidence indicates that "space" as defined has no real existence, because an object is always moving through something. Therefore this sense of "space" is just an ideal which facilitates prediction and such things, but doesn't demonstrate reality..

Quoting tim wood

This was an assignment in a science class, to mark the point of sunrise on the horizon from a fixed point across a few months, demonstrating that the location of the sun's mounting the horizon moves through the year quite a bit. Now, I find more than a few problems with your question, but we can start with this: how is a place/location not real? Is the mark not real? is the location it refers to not real? is the phenomenon demonstrated - and the way it is demonstrated - not real? Let's add "real" to the list of words you need to define.

You appear to be conflating the map and the terrain. My example was a mark on the map, which signifies a location. Let's proceed without the conflation. The mark on the map is real, as a real mark on the map. What does the mark signify? I said a location, "the place where the sun comes up". You seem to agree with me, that there is no such place, no such real location, independent from the map. Is this correct? Do we have agreement here?

If we agree on that, I would say that any location marked on the map is the very same principle. A "location" marks something on the map which has no real existence independent of the map. So for example, if I put an X, and say that the treasure is buried at the X, on the map "X" means a location, but on the ground "X" means what ever is there, according to interpretation of the map. Whether it is a treasure which is there, or whatever, is to be determined, but whatever is there is not "a location", it is a real physical thing. So whatever it is on the ground, is something other than a "location", and the thing on the map, which is said to be "the location" is completely different from what is on the ground because "location" refers to something conceptual, a set of rules intended for finding something on the ground, or determining a thing's position relative to other things.

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Quoting tim wood

There's air and water, possibly jello, all kinds of other media. And in as much as there is no such thing as space, in which these are, they must each itself be uniquely primordial. And how does that work? Whence cometh; where situated? And as to what is in physics, I advert back to the cow in the book, which isn't.

I don't get it. Why do you think there must be something "primordial"? There's all these different substances, water, air, jello, etc., how does "primordial" enter the scene?

Quoting tim wood

And movement isn't necessarily through; but it is "with respect to" or relative to.

Sure, I agree with that, but you are the one who implied that movement was through space when you said: "Seems pretty real to me when I have to go anywhere.". So I was simply pointing out that if movement is through something, it isn't through space. Or what were you trying to say when you said that?

Quoting tim wood

We do not. Sunrise is a well-understood phenomenon. And the location of sunrise equally well-understood, and can for given parameters be marked with a stone. Which, come to think of it, has been a world-wide practice since pre-history.

I don't think the location of sunrise is well understood at all. It is completely subjective, dependent on perspective, and "perspective" is not very well understood.

So I really don't understand how you could mark the location of sunrise with a stone. Are you saying that if you put a stone on the ground, and I went and stood there, I would experience the sun rising through me? That's rhetorical, because I know you said "for given parameters". What do you think is added by giving parameters?

Quoting tim wood

But maybe relsolve it this way. Let's ask the scientists on TPF. Space, time, real? Existing? Or unreal, not existing?

Oh great idea, go ahead, start a thread, I'll read it.

Quoting Metaphysician Undercover

But maybe resolve it this way. Let's ask the scientists on TPF. Space, time, real? Existing? Or unreal, not existing? — tim wood

Oh great idea, go ahead, start a thread, I'll read it.

Me too. But I don't see a resolution on the horizon. :chin:

Could we postulate that as space and time are things we can measure, therefore, they exist? This is summed up in the idea "I think, therefore, I am.' Perhaps this could be re-phrased as 'I measure, therefore, I am!' This is important because unless we can establish our own existence how can we establish things we experience?

Quoting tim wood

You appear to have forgotten the magic phrase, "I (we) don't know." Without it, you're in trouble. For example, "I cannot (do not know how to) drive that car," and, "That car cannot be driven." Big difference, and I assume you see the potential for trouble.

tim, may I ask you what you mean by 'knowing?' I need some more clarification.

Quoting Metaphysician Undercover

If we agree on that, I would say that any location marked on the map is the very same principle. A "location" marks something on the map which has no real existence independent of the map. So for example, if I put an X, and say that the treasure is buried at the X, on the map "X" means a location, but on the ground "X" means what ever is there, according to interpretation of the map. Whether it is a treasure which is there, or whatever, is to be determined, but whatever is there is not "a location", it is a real physical thing. So whatever it is on the ground, is something other than a "location", and the thing on the map, which is said to be "the location" is completely different from what is on the ground because "location" refers to something conceptual, a set of rules intended for finding something on the ground, or determining a thing's position relative to other things.

Yes, i.e., a representation of the physical world in the same way as mathematics is. But mathematics is NOT the physical world. We have to use ciphers in order to organize our experiences.

Quoting Richard Townsend

Could we postulate that as space and time are things we can measure, therefore, they exist?

Space is not something which we measure. We measure attributes like size, volume, and various relations (distance for example) between things. And by the conventions of modern physics we do not measure time either. Time is the measurement, and it is a product of the act of relating movements, or actions, one to another. When Newtonian "absolute time" was replaced with Einsteinian "relative time", time was no longer conceptualized as something measured, and then became only the measurement. The duration of time is completely dependent on the frame of reference, which is artificial.

Quoting Metaphysician Undercover

Space is not something which we measure. We measure attributes like size, volume, and various relations (distance for example) between things. And by the conventions of modern physics we do not measure time either. Time is the measurement, and it is a product of the act of relating movements, or actions, one to another. When Newtonian "absolute time" was replaced with Einsteinian "relative time", time was no longer conceptualized as something measured, and then became only the measurement. The duration of time is completely dependent on the frame of reference, which is artificial.

If space and time cannot be measured then why do they exist? Or are you saying they don't really exist?

Quoting Richard Townsend

If space and time cannot be measured then why do they exist? Or are you saying they don't really exist?

Space and time exist as concepts produced for the purpose of facilitating measurement, and representation of what is measured, just like a coordinate system, which I mentioned above.

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I just came across one of Victor Toth's commentaries on Quora regarding Bell's results. It's the clearest I've ever read.

What are considered hidden variables in physics? Would dark matter be considered as a hidden variable?

No, dark matter has nothing to do with it.
Hidden variables arise in the context of quantum physics, in particular the famous Bell’s Theorem according to which quantum physics is nonlocal.
This is best illustrated by an example from Bell’s book, an example involving socks. Suppose you take a trip somewhere. Upon arrival in your hotel room, you notice that you have only half a pair of your favorite gray socks in your suitcase. From this you instantly infer that the other half must be left behind at home in your socks drawer. The variable representing half a pair of your gray socks was there all along, but it was “hidden” from you for whatever reason.
Now take the analogy to the quantum realm. You have a pair of correlated particles isolated from the environment, say, a pair of electrons. You measure the spin of one of the electrons and you immediately infer the outcome of a spin measurement that might be carried out on that other electron. Could it be that the spin value of the electron, just like the information about your socks, was there all along, as a “hidden variable”?
The answer is a no, for reasons that are mildly technical, but I think I can explain the essence. A spin measurement involves orienting the instrument with respect to which the spin is measured. This orientation need not be known in advance. Yet the spins of the two electrons will be correlated nonetheless. There is no classical physics analogue for this phenomenon. The point is, information in the form of “local hidden variables” that the electrons carried with themselves is not sufficient to account for the correlation between the two electrons under arbitrary orientations of the instruments used to measure them. Additional, “non-local” information is required to account for the observed correlation. Quantum physics is thus manifestly non-local, cannot be explained using hidden variables. (What is absolutely fascinating that despite this nonlocality, quantum field theory is demonstrably and strictly causal, i.e., contrary to some fictionalized accounts or even some misguided popular science explanations, quantum entanglement cannot be used to circumvent the relativistic speed limit or create a time machine. It just does not work that way, which, incidentally, is actually a Good Thing, as an acausal universe would be chaotic and unpredictable, quite possibly unstable).

Quoting tim wood

And this same wind blows through his other arguments. There is no space, but there are all sorts of media through which things move. So if there is not space, what is the account for media - I'd say "presence of" but even that can't be, absent space. And so it goes.

I don't understand. The medium through which a body moves is what it is, whether it be air. water, aether, or whatever. Why do you require "space" to account for the media? It seems to me, like you're just setting the conditions for infinite regress. The moving body evidently exists in something, the medium. But then you insist that the medium must exist in something, "space". If we follow your logic, we'll see that space must exist in something further, and on and on, ad infinitum. You can nip it in the bud by apprehending that space is not required to account for the media.

Reply to jgill

What is absolutely fascinating that despite this nonlocality, quantum field theory is demonstrably and strictly causal, i.e., contrary to some fictionalized accounts or even some misguided popular science explanations, quantum entanglement cannot be used to circumvent the relativistic speed limit or create a time machine ~ Victor Toth.

Although, interestingly, entanglement IS being mooted for creating secure transaction systems that would be theoretically impenetrable even to quantum computers, should one ever be built. This is the basis of 'quantum key distribution'. QKD enables two parties to generate a shared, secret random key. The fundamental principle of QKD is that it's impossible to measure a quantum system without disturbing it. Therefore, any eavesdropper trying to intercept the key will necessarily introduce detectable anomalies. If the key is intercepted, it will be known, and the key can be discarded. Thus, even a quantum computer, which poses threats to traditional encryption methods, can't crack a quantum key if the QKD process is implemented correctly. China's Mucius satellite test was used to establish a secure quantum communication link between China and Austria, spanning a distance of 7,600 kilometers, in 2017 (see story).


Quoting Richard Townsend

how else may entanglement be explained within our current framework of spacetime? It can't, which seems to indicate that spacetime and entanglement are merely human constructs that account for data collection.

I agree with the gist, I think, except for the qualification 'merely' - what's the Feynman quote, 'nothing is "mere"'? But overall I agree that there is an inextricably subjective element in the observations. This conforms with QBism (Quantum Baynsianism) as I understand it.

Quoting Chris Fuchs, Quanta Magazine Interview

Q: Treating quantum mechanics as a single-user theory resolves a lot of the paradoxes, like spooky action at a distance.

A: Yes, but in a way that a lot of people find troubling. The usual story of Bell’s theorem is that it tells us the world must be nonlocal. That there really is spooky action at a distance. So they solved one mystery by adding a pretty damn big mystery! What is this non-locality? Give me a full theory of it. My fellow QBists and I instead think that what Bell’s theorem really indicates is that the outcomes of measurements are experiences, not revelations of something that’s already there. Of course others think that we gave up on science as a discipline, because we talk about subjective degrees of belief. But we think it solves all of the foundational conundrums.

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Quoting tim wood

Your position is, then, that air, water, jello, whatever, as media, simply exist, but not anywhere because there is not any where for them to be?

Location is relative, so where each thing exists is relative to other things. "Space" is a complex concept which human beings use to describe and measure these relations, it is not where these things exist, unless the premise is that "things" are purely conceptual.

Quoting tim wood

But you mentioned measurement, as the representation of what was measured. If my desk is four feet from my bookcase, that is four feet of what? Air? And the air being withdrawn, which is possible, or replaced with water, which is possible, does that alter the distance between desk and case?

I don't see how replacing four feet of air with four feet of water would alter the distance, unless it affected the measuring technique. The question of withdrawing the air to create a vacuum is a more complex issue. And this is the same question as the issue of all the supposed "void space" which is inside a solid substance: it's supposedly inside molecules, and inside atoms, between the parts of these things. But this is not really "void space", as there is things like electromagnetism and gravity there. So this reality serves to help demonstrate the need for an "aether" which was discussed earlier in this thread, as the medium within which these things are active.

Quoting Metaphysician Undercover

Space and time exist as concepts produced for the purpose of facilitating measurement, and representation of what is measured, just like a coordinate system, which I mentioned above.

Surely, if space and time exist as concepts, they exist!

Quoting tim wood

An excellent TPF best kind of question! Nothing complicated or difficult. Let's try a short-cut: if in consideration of my actions, you aver that I have knowledge, then I have knowledge, and I know about what I have knowledge of. And of course we may both be wrong. But I invoke knowing in this context to distinguish between them what knows and them that don't. And those who do not know will often argue in an expanded and concealed way that because they don't know, they know. E.g., it isn't X therefore it must be Y. And it can get pretty twisted, as with out interlocutor in this thread, viz.,

This statement does not seem to have any consistency. You seem to be contradicting yourself.

Quoting Wayfarer

I agree with the gist, I think, except for the qualification 'merely' - what's the Feynman quote, 'nothing is "mere"'? But overall I agree that there is an inextricably subjective element in the observations. This conforms with QBism (Quantum Baynsianism) as I understand it.

I was using the word 'merely' to denote that it seems there exists no pre-existing 'grand scheme' external to our perceptions so, that it is we who have a participatory role in the formation of reality That's not to downplay our role but to point out it is a matter of what is right in front of us. This goes back to what I was saying earlier about us not being able to be directly be aware of the true complexity of nature but may only construct a kind of 'subject' workspace within which to operate. To claim there may be some kind of grand scheme in place is meaningless, I contend, since a 'scheme' implies design.

Quoting tim wood

Your position is, then, that air, water, jello, whatever, as media, simply exist, but not anywhere because there is not any where for them to be? But you mentioned measurement, as the representation of what was measured. If my desk is four feet from my bookcase, that is four feet of what? Air? And the air being withdrawn, which is possible, or replaced with water, which is possible, does that alter the distance between desk and case?

Yet, without measurement, nothing may exist. Even thinking is measurement, I would argue, or put more simply, 'noticing things', which is what we are all doing right now, is it not? Without this pre-existing condtion, no discussion would be possible.

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Quoting tim wood

We have to acknowledge that MU is narrowly correct..

What does this mean, "narrowly correct"?

Quoting tim wood

But he would deny space per se. If what separates my desk and bed is four feet of air, and there is no space, then removing the air is removing the medium in/of which the measurement is made, and thus my bed and desk then touching, Yes?

How would you remove the air between them, if not by either pushing them together, or displacing it with something else? Anyway, I don't see how this is relevant, because as I explained already, there is necessarily a medium even between air molecules. So even if you could remove all the air molecules this would still leave a medium.

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Quoting tim wood

I forget, please remind me. The distance from my bureau to my desk is four feet. What is between them?

Air. How could you forget, you just asked about the possibility of removing the air?

Quoting tim wood

And it is possible we simply understand two - at least two - different things in our respective usages of "space." Perhaps you could offer your definition or if you claim there's no such thing, then so state.

It appears you are having difficulty remembering simple things tim. You already asked me for a definition of "space".

Quoting Metaphysician Undercover

So, from my OED, the first definition of "space" reads like this: "a continuous unlimited area or expanse which may or may not contain objects etc."

Then I went on to say that this supposed "continuous unlimited area or expanse" is just an ideal, there is no such thing independent of the human minds which employ this ideal in there activities..

Quoting Metaphysician Undercover

What I've been telling you, is that this does not refer to anything real, independent, in the world. It is an ideal which facilitates all sorts of human activities of conceptualizing, measuring, etc.. Take your example of movement now.

Quoting tim wood

Mine is too simple: it is that which remains when every thing is removed: the space, e.g., between my bureau and my desk. And when things are present, what they occupy.

This provides another example of why I say "space" is just an ideal which does not refer to anything real. It is impossible to remove everything from any area. We are always left with something in that area, gravity, whatever is represented by various fields, etc.. It seems like all normal usage of "space" renders it as something ideal which cannot actually be obtained in the real physical world.