Is the model presented in the thread consistent with QM?

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Discussion Overview

The discussion centers on the consistency of a mathematical model with quantum mechanics (QM), specifically examining the implications of measurement angles and the relationships between different parameters in the model. The focus is on the mathematical formulation and its alignment with QM principles.

Discussion Character

  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant argues that the model's measurement results vary with the parameter ##\lambda##, suggesting inconsistency with QM, particularly when measuring polarization at specific angles.
  • Another participant proposes that the model may be nonlocal, indicating potential consistency with QM, referencing a specific equation that involves both measurement apparatus properties.
  • Concerns are raised about the clarity and consistency of the mathematical definitions used in the model, particularly regarding the reuse of symbols and their implications for the equations presented.
  • There is uncertainty regarding the derivation of a specific formula, with participants questioning its local versus nonlocal nature and its application to different polarizer settings.

Areas of Agreement / Disagreement

Participants express differing views on whether the model is consistent with QM, with some suggesting nonlocality as a potential resolution while others highlight inconsistencies. The discussion remains unresolved regarding the model's validity.

Contextual Notes

Participants note potential issues with the reuse of symbols in the mathematical expressions, which may lead to confusion and errors in interpretation. The implications of specific measurement angles and their effects on the model's predictions are also highlighted as areas of concern.

msumm21
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TL;DR
Seems that a model in a recent paper is not consistent with QM, this post includes an example case and questions how it can be consistent.
I started another thread on this but it went off into other topics. Hoping to focus on the math here, specifically whether or not the model presented in here is consistent with QM.

Let's measure the polarization at the same angle ##\alpha = \beta = \pi/3## (##\varphi_1=0, \varphi_2=\pi/2##). Now ##\delta_1=\pi/3,\delta_2=-\pi/6## and hence we have ##A=1## when ##\lambda <= 1/4## and ##B=-1## when ##\lambda <= 3/4## so that the A,B measurement results matching or not is not guaranteed, but varies with ##\lambda## which is inconsistent with QM.

Even more odd, changing the measurement direction to say ##\alpha=\beta=0## changes this conclusion as if there's a preferred direction in space. Or did I miss another exception?
 
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Moderator's note: This thread is a reopen of a previous thread. Please keep discussion in this thread exclusively focused on the consistency of the referenced mathematical model with QM.
 
Then I will repeat what I already said. I think the model is in fact nonlocal, so it has a potential to be consistent with QM. This is seen in the paragraph around Eq. (9). In particular, before (9) it says that it uses
$$\delta = \alpha +\pi/2 -\beta$$
It's not clear to me how exactly did he get this formula, but this formula is nonlocal. It is nonlocal because ##\alpha## is a property of one apparatus, while ##\beta## is a property of the other apparatus. Or if the author still claims that this formula has a local origin, it would help if he could better explain how did he obtain this formula, because to me it's not clear from the paper.
 
Last edited:
Demystifier said:
It's not clear to me how exactly did he get this formula, but this formula is nonlocal
Looks like he's considering the special case where the 2nd polarizer is set at ##\alpha + \pi/2## so that the equation gives the angle ##\delta## between ##\varphi_2## and the polarizer. I'm unconfident because this is reusing the same symbol in different ways: using ##\beta## here to be what was originally defined to be ##\varphi_2##.

This may be the source of another error, because it looks like equation 9 is later used as if ##\beta## is the polarizer setting again (whereas it was really ##\varphi_2## in this equation) and then using this equation for general polarizer settings whereas the equation was made for 90deg offset polarizers.
 
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