Bell's Theorem Correlations Velocity

[Rodsw]

How do you know that?

That's incorrect. Bell himself showed that a hidden variable formulation of individual detections is compatible with QM. What's been refuted is Bell-type LRHV formalizations of quantum entanglement. Whether or not this is general is an open question, afaik.

By LRHV you mean Local Realism Hidden Variable? So Bell showed a non-local hidden variable is possible. Is this what you are saying?

Well, no. At least not necessarily. But I don't know what the majority view is. And, anyway, the majority view doesn't matter in science, because the majority view might be a matter of taste due to social pressures or whatever. The point is that it's an open question, and that neither view has been definitively demonstrated.

One is free to assume that the correlations are due to nonlocal communications between entangled particles, or due to relationships produced via common causes, ie., local transmissions.

Or due to the equations only in Anti-Realism formulations.

Ok, I'll remember this always. Can we close this thread now?

Ok. [CLOSE] Thread [/CLOSE]

 

[ThomasT]

By LRHV you mean Local Realism Hidden Variable?

Yes, this was specified in a previous post in this thread.

So Bell showed a non-local hidden variable is possible. Is this what you are saying?

No. Bell showed that a local hidden variable description of individual detections is compatible with QM. The problem is with joint detections in entanglement setups, and wrt those then Bell-type LRHV models are nonviable.

Or due to the equations only in Anti-Realism formulations.

I'm not sure what you're saying here. I consider standard QM to be nonrealistic, and therefore neither local nor nonlocal.

 

[Rodsw]

Yes, this was specified in a previous post in this thread.

No. Bell showed that a local hidden variable description of individual detections is compatible with QM. The problem is with joint detections in entanglement setups, and wrt those then Bell-type LRHV models are nonviable.

But whenever we are talking about Bell and Bell's Theorem. We automatically assume entanglement. Therefore it doesn't make sense why you had to mention about hidden variable in individual detection. It's what confusing me from the start what you are saying.

I'm not sure what you're saying here. I consider standard QM to be nonrealistic, and therefore neither local nor nonlocal.

If it's neither local nor nonlocal. Then your statement "One is free to assume that the correlations are due to nonlocal communications between entangled particles, or due to relationships produced via common causes, ie., local transmissions." is wrong or invalid.

I just want to learn how to say things to a beginner. I may use the following way of explaning it:

To explain quantum entanglement, there are 2 approaches. The realism and anti-realism approach. For the realists, "One is free to assume that the correlations are due to nonlocal communications between entangled particles, or due to relationships produced via common causes, ie., local transmissions." This approach is for Bohmian Mechanics and Objective Collapse Interpretations.

For the Anti-realists. One is free to assume that the correlations are due to the equations and one must not have any picture of matter having definite position and spacetime being really there. This is the Copenhagen interpretation or the orthodox.

There is a third way to look at it. The approach of the Many Worlds or the correlations a result of many branches matching up.

Do you agree with the above classifications. I may write a magazine article about it or even a book "Idiot's Guide to Bell's Theorem and Quantum Entanglement" so I need accurate statements.

 

[ThomasT]

But whenever we are talking about Bell and Bell's Theorem. We automatically assume entanglement.

Ok.

Therefore it doesn't make sense why you had to mention about hidden variable in individual detection. It's what confusing me from the start what you are saying.

Just to point out that hidden variables aren't ruled out wrt individual detections. That not only can you assume that hidden variables determine individual detections, but you can make an LRHV model wrt individual detections that's compatible with QM and experiments.

But keep in mind what I said about entanglement correlations (joint detections). They're, presumably, not determined by the same hidden variable that determines individual detections. Presumably, coincidental detections aren't determined by a hidden variable, but rather a hidden constant, ie., an underlying parameter (a relationship between entangled particles) that doesn't vary from entangled pair to entangled pair the way that the the variable determining individual detection does.

If it's neither local nor nonlocal. Then your statement "One is free to assume that the correlations are due to nonlocal communications between entangled particles, or due to relationships produced via common causes, ie., local transmissions." is wrong or invalid.

I said that I consider the quantum theory to be neither local nor nonlocal. However you choose to interpret QM, if the interpretations are unfalsifiable, which they all are afaik, then you're free to assume that entanglement correlations are due to nonlocal communications between entangled particles, or due to relationships produced via common cause, ie., local transmissions.

I just want to learn how to say things to a beginner. I may use the following way of explaning it:

To explain quantum entanglement, there are 2 approaches. The realism and anti-realism approach. For the realists, "One is free to assume that the correlations are due to nonlocal communications between entangled particles, or due to relationships produced via common causes, ie., local transmissions." This approach is for Bohmian Mechanics and Objective Collapse Interpretations.

The latter is also for the local realistic approach which says that the correlations are due to relationships between entangled particles produced via common origin or common influences transmitted via local channels.

For the Anti-realists. One is free to assume that the correlations are due to the equations and one must not have any picture of matter having definite position and spacetime being really there. This is the Copenhagen interpretation or the orthodox.

It's not that you can't have some sort of picture about what's happening in the underlying reality (eg., standard QM incorporates, and was developed from, all sorts of classical conceptions), but that there's no way to verify or falsify any particular picture of the underlying reality.

There is a third way to look at it. The approach of the Many Worlds or the correlations a result of many branches matching up.

I wouldn't bother with this third way of looking at it. At least not wrt beginners.

Do you agree with the above classifications. I may write a magazine article about it or even a book "Idiot's Guide to Bell's Theorem and Quantum Entanglement" so I need accurate statements.

I think that if you're going to write a beginners guide to Bell's theorem and quantum entanglement, then you need some input from people more knowledgeable than me. I learned what I've learned haphazardly, over several years, and, while I think I understand all of the (at least most of the relevant) issues involved, I might be quite wrong in my current understanding. So, hopefully, some more knowledgeable people will weigh in on this to help you out.

Anyway, I hope that our brief discussion has helped clarify some things for you. If you have any further considerations, then please present them, and if I think I know something about them then I'll reply. Otherwise, as mentioned, hopefully your questions/considerations will be addressed by PF science advisors/mentors or maybe some of the non-staff physicists that contribute to PF.

 

[Rodsw]

Ok.

Just to point out that hidden variables aren't ruled out wrt individual detections. That not only can you assume that hidden variables determine individual detections, but you can make an LRHV model wrt individual detections that's compatible with QM and experiments.

But keep in mind what I said about entanglement correlations (joint detections). They're, presumably, not determined by the same hidden variable that determines individual detections. Presumably, coincidental detections aren't determined by a hidden variable, but rather a hidden constant, ie., an underlying parameter (a relationship between entangled particles) that doesn't vary from entangled pair to entangled pair the way that the the variable determining individual detection does.

I said that I consider the quantum theory to be neither local nor nonlocal. However you choose to interpret QM, if the interpretations are unfalsifiable, which they all are afaik, then you're free to assume that entanglement correlations are due to nonlocal communications between entangled particles, or due to relationships produced via common cause, ie., local transmissions.

Ok Thanks. I understood better now the position of the orthodox. In the orthodox. They just deal with quantum theory. And since the interpretations are unfalsifiable.. we are free to picture them by for example, like what you said that entanglement correlations are due to nonlocal communications between entangled particles, or due to relationships produced via common cause, ie., local transmissions.

While there are other interpretations like Many Worlds and even Consistent Histories which can explain the correlations without resorts to relationships produced via common cause, ie., local transmissions . Let's focus on the non-local communications between entangled particles variety and the subject of this thead. That is. I was asking if the correlations have velocity. After exchanging many ideas with you. I can present it clearer now. Assuming the quantum correlations are due to nonlocal communications between entangled particles.. this automatically invokes the Bohmian interpretation and Objective Collapse (I think you agree).

So what I was wondering was if wave function were real. It doesn't make sense that they are instantaneous at 92 billion light years end to end. Meaning they should have speed.. it's like in the past where one assumes light has infinite velocity... but we know it doesn't. So Bohmian wave function needs to have speed limit of say 100 times the speed of light.

Therefore learning all these facts from start of thread. My real question was.

In Bohmian mechanics where the wave functions are real. It doesn't make sense they are instantaneous. Nothing in nature can occur end to end at 92 billion light years instantaneously. It has to have a velocity. At this point. I know it is beyond us since lorentz violations need to occur. So let's just wait for Bohmians to reply. If there would be none. Then let's just wait for Bohmians to discuss them and ask the question at that future thread.

I think you agree now with my understanding. You spent one year studying Bell's Theorem day and night talking with physicists all the time so you are more advanced than any novice.
Thanks.

The latter is also for the local realistic approach which says that the correlations are due to relationships between entangled particles produced via common origin or common influences transmitted via local channels.

It's not that you can't have some sort of picture about what's happening in the underlying reality (eg., standard QM incorporates, and was developed from, all sorts of classical conceptions), but that there's no way to verify or falsify any particular picture of the underlying reality.

I wouldn't bother with this third way of looking at it. At least not wrt beginners.

I think that if you're going to write a beginners guide to Bell's theorem and quantum entanglement, then you need some input from people more knowledgeable than me. I learned what I've learned haphazardly, over several years, and, while I think I understand all of the (at least most of the relevant) issues involved, I might be quite wrong in my current understanding. So, hopefully, some more knowledgeable people will weigh in on this to help you out.

Anyway, I hope that our brief discussion has helped clarify some things for you. If you have any further considerations, then please present them, and if I think I know something about them then I'll reply. Otherwise, as mentioned, hopefully your questions/considerations will be addressed by PF science advisors/mentors or maybe some of the non-staff physicists that contribute to PF.

 

[ThomasT]

You spent one year studying Bell's Theorem day and night talking with physicists all the time so you are more advanced than any novice.

That's not true, and I didn't say that. My understanding (such that it is, a bit more than novice) was learned intermittently over several years. One person at PF who knows a lot about Bell's theorem and associated experiments is DrChinese. Check out his posts and his website (if you haven't already). Actually most of the PF science advisors (Jesse, etc.) can clear up any difficulties you might have with Bell's theorem much better than I can.

Anyway, good luck in your quest. It's been fun discussing with you. By the way, you might research the threads and papers of Demystifier also. He's the resident PF expert on the Bohmian interpretation.

And I almost forgot, there's the links that Edgardo and bohm2 posted. Good stuff