I A new realistic stochastic interpretation of Quantum Mechanics

[DrChinese]

... this measurement stops any causal influence between A and B for $t > t_1$.

...What Barandes proved is that QM formulated as a unistochastic process satisfies his new principle of "causal locality" which states that, if two localized systems remain spacelike separated during the time of a given physical process, they do not causally affect each other, in the sense that the conditional probabilities of one particle do not depend on what happens to the other.

His new principle of "causal locality" is absurd. Precisely the kind of mistake (i.e. assumption) EPR made.

EPR: They made their conclusion based on the ability to predict B after measuring A. They didn't look at the case of an A, B and C - which Bell showed was necessary.

Barandes: A & B are locally causal by his "new" and useless definition - which is why no one will ever need it for anything. It has long been known that a measurement on A does not affect the marginal probabilities of B. But the same is not true of measurement pairs on A & B and C & D (entanglement swapping, usually with 3 parties). With A(lice) & B(ob) remote, the marginal probability of their pairwise correlation is dependent on a remote swap operation by Victor. Causal locality is also not true for GHZ measurements (A, B and C by 3 parties).

The point is: If you define things so you cannot falsify your hypothesis, then you haven't accomplished anything. All Barandes' definition is good for is, in essence, stating that remote signaling is not possible. OK, everyone already agrees on this anyway.

Meanwhile: virtually everyone instead accepts the Bell definitions. That is why Bell is so important! It is easy to understand that a measurements on A and B are not separable (not in a Product state) as to their outcomes. Which they must be, if there is no mutual influence of some kind.

---

Furthermore: trying to cast Bell correlations in a statistical light is fundamentally flawed anyway. That is completely ignoring the entire lesson that EPR did successfully make: That ANY 1 individual measurement on A could lead to a perfect prediction for B. There is no marginal probability there. If the Barandes premise is that there is no connection (causal or otherwise!) whatsoever between A and B, then he has the problem of explaining how that perfect correlation arises - at any spin angle across 360 degrees! We're back to predetermination, and the Bell argument showing that there are no possible predetermined outcomes that are consistent with QM. There are no statistical averages to consider. A huge hole.

In other words: Barandes, as a scientist proposing a novel viewpoint, must subject his work to the most stringent of conditions and possible objections. He is giving himself a pass here, and so is anyone else who cannot address critiques on his position.

 

[DrChinese]

Presumably you don't need non-local communication to explain why correlations in an entanglement experiment might be degraded due to external noise.

"Communication"? A poor word choice, as it implies signaling.

"Degraded" correlations? Bell inequalities/correlations have been demonstrated to over a hundred SD. So who* is trying to bring noise into the equation, when it is obviously not theoretically relevant.


*And why...?

 

[lodbrok]

His new principle of "causal locality" is absurd.

Is this an emotional reaction, or is it based on something wrong with his definition? The definition is quite straightforward: https://arxiv.org/pdf/2402.16935

Causal influences should not be able to propagate faster than light.

What is absurd about this?

 

[PeterDonis]

I wasn't trying to explain Bell violations

Yes, and my point is that you need to if you are going to claim that your explanation is correct, because Bell inequality violations occur in nature. We've shown that with experiments. So any mental model you have that can't explain Bell inequality violations can't be right. And the mental models you suggested, like "how clocks become unsynchronized", can't explain Bell inequality violations. They satisfy the premises of Bell's Theorem. You need an explanation that violates at least one of those premises.

 

[iste]

Yes, and my point is that you need to if you are going to claim that your explanation is correct, because Bell inequality violations occur in nature. We've shown that with experiments. So any mental model you have that can't explain Bell inequality violations can't be right. And the mental models you suggested, like "how clocks become unsynchronized", can't explain Bell inequality violations. They satisfy the premises of Bell's Theorem. You need an explanation that violates at least one of those premises.

The comment was not putting forward a model or explanation of quantum mechanical behavior, it was trying to stimulate an intuition that if you have a non-factorizable but spatially separated system of any kind and disturb one of the parts so that it becomes factorizable, there is no logical necessity that the disturbance must be somehow causing some change at a spatially distant part. I could have literally used any example of any kind of behavior with no relation to quantum mechanics whatsoever. I could have used an example of people behaving in correlated ways and then one of them getting disturbed so that they are no longer correlated. You have misread what I was saying.

"Communication"? A poor word choice, as it implies signaling.

"Degraded" correlations? Bell inequalities/correlations have been demonstrated to over a hundred SD. So who* is trying to bring noise into the equation, when it is obviously not theoretically relevant.

See above.

 

[physika]

But lets suppose reality is emergent in some way,

Emergent from what ?
That "what" have to exist to give rise to that "reality"
Or that "what" simply is the real.

......

 

[PeterDonis]

The comment was not putting forward a model or explanation of quantum mechanical behavior

Yes, it was:

it was trying to stimulate an intuition that if you have a non-factorizable but spatially separated system of any kind and disturb one of the parts so that it becomes factorizable, there is no logical necessity that the disturbance must be somehow causing some change at a spatially distant part.

This is putting forward a model or explanation of quantum mechanical behavior.

If you seriously don't think that's the case, then what are you doing even posting in this thread? This thread is about a proposed interpretation of QM. Should I just delete all your posts as off topic and ban you from further posting in this thread?

 

[iste]

But the same is not true of measurement pairs on A & B and C & D (entanglement swapping, usually with 3 parties). With A(lice) & B(ob) remote, the marginal probability of their pairwise correlation is dependent on a remote swap operation by Victor. Causal locality is also not true for GHZ measurements (A, B and C by 3 parties).

I'm not sure this is true. I don't think any signalling across space is allowed so these phenomena cannot be about marginal probability distributions.

 

[iste]

Yes, it was:


This is putting forward a model or explanation of quantum mechanical behavior.

If you seriously don't think that's the case, then what are you doing even posting in this thread? This thread is about a proposed interpretation of QM. Should I just delete all your posts as off topic and ban you from further posting in this thread?

No, it isn't. If you read my conversation with Sambuco back to (or forward from) the initial comment (#604) he made that I replied to, you will see that the topic of the whole conversation is whether Barandes' formulation entails "nonlocal updating", in Sambuco's words. In other words, does measurement lead to a direct nonlocal change in the behavior of the system in Barandes' formulation. Sambuco was probing whether measurement leads to changes in the transition matrices or analogues of collapse which you would think of as some kind of nonlocal updating. We were both comparing to other kinds of formulations such as Bohmian mechanics where these things are explicit. Obviously there is something to be said for what collapse in QM means and whether it is relevant for Barandes' formulation. So you can see that we are having a discuasion probing whether different aspects of the formalism constitute aome kins of "nonlocal updating" and to what extent that could be interpreted physically. At I think post #665, Sambuco suggests that measurement-induced factorization should be considered "nonlocal updating" whoch is an interesting point. "Nonlocal updating" may be ambiguous. For instance, no-signalling or dependencies due to the quantun potential may be kind of transparently straightforward, but this may not be the case for everything. For instance; similar to what I mentioned in post #699, it can be ambiguous whether a correlation on its own across space entails some kind of non-local updating. Afterall, this can happen classically. Clearly that question may depend on other factors: e.g. does the correlation have a local common cause? Does the underlying microscopic deacription have some kind of non-local updating? etc, etc. Is a local explanation prima facie just seemingly implausible (e.g. like in the perfect spin case)? I think the loss of non-factorizability could possibly come under this kind of category where there is ambiguity; and in any case, I had never heard the loss of factorization being discussed as an instance of "nonlocal updating" before so I had no context that prescribes how to think of that. So I put forward my intuition that a loss of non-factorizability does not imply a kind of non-local updating, and there are many examples of analogies that you could say may support this intuition like the clock case. There doesn't seem to be anything further about the loss of factorization which would make these examples difficult - in contrast to, say, the bell spin correlations which have a unique structure which make them difficult to conceptualize in any other local sense. But where ia the uniaue structure in the loss of factorization that would analogously prohibt the use of auch analogies? In Barandes papers somewhere he refers to non-factorizability as a kind of "generic, model-independent" way of talking about interactions, and therefore correlations. So there seems to be nothing special in this description, and my intuition would be that the fact that entanglement correlations can get degraded due to external noise wouldn't be really an example of "non-local updating" either. It just seems to be a loss of correlation due to noise, which you don't need any extra-special mechanisms to explain, like in the clock case.

So hopefully you will see that my conversation with Sambuco has been a substantive, productive one about a genuinely relevant topic regarding whether "non-local updating" is a part of Barandes' formulation or not, ans the nuanced ambiguities that can occur in considering what can be seen as "non-local updating" and the use of thought provoking examples to argue for or against some point in which there is a standing ambiguity - is the loss of non-factorizability due to measurement an example "non-local updating"? I don't think it is, and as I said before in post #686, the loss of non-factorizability seems to actually be required to stop the measurement "non-locally updating", and coincides with Barandes' "no-signalling analogue result in the model.

 

[PeterDonis]

Thread closed for moderation.

 

[berkeman]

After a Mentor discussion, this long thread has run its course and will remain closed. Thanks to all who contributed.