A Is delayed choice remote entanglement of photons derived from TDSE?

[Demystifier]

Normal NRQM is not one single element, such as the SE. There are many such elements that make up QM. Picking SE and saying "that's where everything comes from" is not accurate.

Everything comes from a few axioms (or rules), the Schrodinger equation being one of them. See e.g. https://www.physicsforums.com/insights/the-7-basic-rules-of-quantum-mechanics/

 

[Demystifier]

The same should occur naturally with Interpretations of QM. Many supply specific mechanisms or claims that can now be refuted.

I strongly disagree.

For example, some believe that MWI cannot be local, even though it is usually labeled "local". But it would still be a good interpretation even if it were labeled "nonlocal". That would mean it evolved to match the experimentally demonstrated and generally accepted existence of quantum nonlocality. (I am not arguing for or against a particular interpretation). This paper is an example of nonlocal MWI, modified to be in concert with the GHZ experiment (which demonstrates quantum nonlocality). That's the scientific method at work as well.

That's not a good example, because the true issue with MWI (as with the standard QM too) is what it means that MWI is "local" or "nonlocal". This is more philosophy than the scientific method in the narrow sense.

 

[Demystifier]

I am denying the important new developments in modern entanglement theory (already listed) were deduced directly with help from the SE. They weren't.

I think we all agree with that. But do you agree with the rest of us that SE was nevertheless used indirectly? And if you agree, why is that important?

 

[mattt]

TL;DR Summary: Is theory around Delayed Choice remote polarization entanglement swapping of photons derived from TDSE or TISE?

That's a strange question, isn't it?

Those experiments are explained by non-relativistic quantum mechanics, the results of those experiments are predicted by non-relativistic quantum mechanics.

The dynamics in non-relativistic quantum mechanics is defined by the Schrodinger equation (plus update of state after measurement).

So, obviously, the answer to your question is: yes.

By the way, there is no "theory" in those experiments different than non-relativistic quantum mechanics and, optionally, quantum field theory.

 

[PeterDonis]

some believe that MWI cannot be local, even though it is usually labeled "local". But it would still be a good interpretation even if it were labeled "nonlocal".

the true issue with MWI (as with the standard QM too) is what it means that MWI is "local" or "nonlocal". This is more philosophy than the scientific method in the narrow sense.

One more time: interpretations are off topic in this thread.

 

[DrChinese]

A. What new theory? Perhaps my reading was superficial, but I haven't noticed that you proposed (or cited a paper about) a new theory.

B. Yes, Born rule is also a cornerstone of entanglement theory. (HUP maybe not so much, because it's derived from more fundamental principles.)

C. I think we all agree with that. But do you agree with the rest of us that SE was nevertheless used indirectly? And if you agree, why is that important?

D. Or to put it blatantly, I have no idea what's your point in this whole thread.

A. I listed those in an earlier post. GHZ, Delayed Choice/Remote Entanglement Swapping (references provided in post #1): none of these existed as theoretical ideas until the 1988 to 2000 time period. And numerous others mentioned here as well.

Surely you must believe that as new cosmological experiments provide new data points, and theory must be added to match, that some previous theories/concepts become untenable. What am I saying different here?


B. I don't think Born rule is referenced so much in the latest entanglement theory. But yes, it is relevant even if it is not a "cornerstone". Again, any reference you have that can show otherwise (directly, not indirectly) would be appreciated.

And just to be clear: I have provided a pretty solid list of seminal papers that build us up to today regarding entanglement. EPR, Bohm, Bell, CHSH, Aspect et al being what I call the old line papers. Hong-Ou-Mandel, GHZS, Bennett-Peres-Wooters, multiple Zeilinger-Ma-Pan teams being the more modern. Of course this is not exhaustive. This is NEW theory, NEW experiment. So pre-existing interpretations and explanations MUST adjust. Again, this is basic scientific method.


C. Sure, the SE is down there somewhere. But a new (or pre-existing!) interpretation - one that is fully consistent with the kinds of quantum behavior that the SE models in textbooks - need not be consistent with the works I mention. This is our point of departure in this thread.

The SE equations largely ceased to be a relevant tool - when discussing or developing entanglement theory/experiment - approximately after Bohm's work in the 1950's. I have a 1958 edition of his "Quantum Theory" (1951) that I received as a gift. On page 618 of 628, something akin to a Bell state appears (this is of course pre-Bell). It is in context his famous spin basis version of the EPR paradox (page 611). And yes, the SE is discussed in quite some detail earlier in the book. (So are various methods using the Heisenberg picture, Hamiltonians, Dirac functions, Born approximation, etc. etc.)

So is this early Bell state a result of calculations using the SE? I guess you could say so. But that version of a Bell state doesn't imply everything that came later! In fact, Bohm specifically mentions that the experimental implementation was not currently possible; and it was not clear what the result might be - whether or not the quantum mechanical prediction of perfect EPR type correlations would be validated.

Bell of course doesn't use the SE in his 1964 paper at all. So the Bohm book is the last direct connection (assuming you agree that it is a direct connection) between the SE and a Bell state representation. Nothing of the SE after Bohm was critical to the (heretofore listed) development of entanglement theory. At least nothing in the historical record I am aware of.


D. So the $64,000 question: why this thread?

As I have said: there have been a lot of developments in entanglement theory that must be addressed in ALL interpretations of QM that expect to remain viable. Entanglement theory - a small subset of QM - is the area in which most interpretations begin to struggle. So if a particular interpretation of QM is able to replicate the predictions of QM in many areas - such as the SE, Born rule, or any other subset of the rules of NRQM for that matter - that does NOT automatically imply that they can reproduce ALL the predictions of the current complete Quantum Mechanical canon.

If the bar is set to 1951 (and the book of Bohm, important as it was): well, that was 73 years ago. If we were comparing 1951 cosmology to 2024 cosmology, everyone would laugh. But in this thread, no one seems to see the humor in discussing the SE (1926) as compared to today's QM. Two different animals.

 

[PeterDonis]

Sure, the SE is down there somewhere.

In other words, you already have what you say you have been asking for: a treatment of these experiments using NRQM that relies on the SE. So what are we having this thread for?

But a new (or pre-existing!) interpretation

there have been a lot of developments in entanglement theory that must be addressed in ALL interpretations of QM that expect to remain viable.

This thread is not about intepretations. If you have something you want to discuss about interpretations and what's missing from them, that (a) belongs in the interpretations subforum, and (b) is irrelevant to the question of whether the SE is involved, that question is a simple question about what NRQM, independent of any interpretation, includes.

 

[PeterDonis]

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[PeterDonis]

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