Bell Controls - Paper

(Control against known or unknown biases in experiments)

By James Tankersley Jr, 2023-02-10 (updated 2023-02-10)

Attributions:

Guidence from Chantal Roth and Richard Gill. Review by Mark Payne and Pierre Leroy.

Summary


"But how do you know?" Marge Gunderson, Fargo, 1996

Computer simulations demonstrate that tests of Bell's Inequalities produce valid results in "naive" ideal conditions, but are challenged by the ease that false results can be generated by a host of factors with the experiment itself or the environment. This paper proposes control tests as means to confirm the absence of known or unknown effects that could invalidate the test results (causing either false positive violations or false negative lack of violations).

Ideal tests of Bell's Inequalities [25] detect the difference between particles that have no definite polarization angle (or spin) until measured, and then adopt polarization of (or opposite of) a deflector device (a philosophy attributed to quantum theory, but criticized as paradoxical by ERP [1]). Versus particles that have a definite polarization angle (or spin) before deflection and detection, a property (or "variable") known only to the particle itself until external measurement (a philosophy attributed to Einstein in his EPR paper and clarified by Bohm).

Control Test Criteria below is proposed as a requirement for settling the issue of, in the language of J.S. Bell, "the Nature of Reality" of the very small.

Control Test Criteria

(Proposed Gold Standard for Bell Tests, version 0.9944)


A Bell's Inequalities Experiment should demonstrate that it does not return biased results and is capable of producing both strong violations and clear non-violations. This is demonstrated by passing both control tests, or a combination of Experiment results and control tests.


(If the Experiment produces strong violations, then a Clear Non-Violation control test is also required. If an Experiment produces clear non-violations, then a Strong Violation control test is also required.)


Requirements for Control tests:

1. Use a statistically significant trial size.

2. The starting point of the Experiment is defined as the point immediately after the Experiment's source emitter, or after the control test's source emitter and appartus to condition particles for control testing.

3. Control test may use their own source emitter and apparatus to condition particles before entering the starting point of the Experiment.

4. The Experiment may not be altered in any way from the point particles enter the Experiment starting point through deflector to final detection.

5. Clear Non-Violation control test must emit orthogonal or antiparallel particle pairs that are not correlated with nor have knowledge of Experiment's conditions after the starting point including deflector polarization angles.

6. Strong Violation control test may have full knowledge of Experiment's conditions including deflector polarization angles and the nature of apparatus that might rotate particle polarizations between starting point and deflector. 

 

Recommendations for control tests:

1. Clear Non-Violation control test may be setup to generate clear non-violations by emitting classical clone particle pairs such that each new (orthogonal or antiparallel) particle pair is emitted pre-polarized to a known, randomly selected polarization axis. 

2. Strong Violation control test may be setup to generate strong violations by emitting quantum analogs such that each new (orthogonal or antiparallel) particle pair is emitted pre-polarized such that one of the particles will have a polarization angle that exactly matches or exactly opposes its deflector angle at the time that the particle reaches the deflector. This may also require anticipating and correcting for any polarization rotation caused by the Experiment between starting point and deflector. 

3. Control tests for biases should take precedence over exotic mechanisms to account for exotic loopholes. (Simplify the Experiment design if neccessary to accomidate control testing).


Experiments that meet control test requirements can be assumed to be able to return unbiased results that settle the EPR question. Experimental Violation of Bell's Inequalities indicates a win for Quantum Philosophy. Non-Violation of Bell's Inequalities indicates a win for Classical Philosophy.

Referr to "Bertlemann's Socks and the Nature of Reality", J.S. Bell 1980 [25] for an eccessible explaination of his 1964 paper "On the Einstein Podolsky Rosen Paradox" [11] that explains how to experimentally test Einstein's EPR proof [1] 

Context

Bell's Inequalities is a test to determine the true nature of the very small [25]. Are properties of fundamental particles (like polarity and spin) random until measured as Quantum Mechanics (QM) argues? Or do particles have specific properties  (like polarity and spin) before they are measured, as Einstein Podolsky and Rosen (EPR) argue? Computer simulations [13] of CHSH/Eberhart tests appear to confirm that Bell's Inequality tests can conclusively detect the difference between QM vs EPR modeled reality. (Quantum [QM] models clearly violate Bell's Inequalities and classical [EPR] models clearly do not).   However, computer simulations of classical particles can also be made to clearly and strongly violate Bell' Inequalities, mimicking quantum modeled results.

False violations can occure from selectively filtering out photons or electrons based on how their initial polarity or spin angles compare to the polarity angle of its Polarizing Beam Splitter (PBS) or magnetic field deflector. Malus Loss favors loss of particles with "intermediate angles" (niether parallel to nor opposite of the deflector, refered to as "intermediate angles" in J.S.Bell's Bertlmann's Socks paper [25]).

False violations can also occur without loss, if non-Bell Violating polarization or spin angles ("intermediae angles") are Rotated toward Bell violating polarization or spin angles (parallel or opposite of deflectors).

Control tests may be used to detect false Bell violations caused by known or unknown effects on classical particles. Control tests involve sending classic particles through the test, emitted with pre-defined polarity or spin angles designed to violate or not violate, proving the experiment is capable of both, is not fundamentally flawed and appears to be free of known or unknown biases. 

References:


[1] Einstein–Podolsky–Rosen paradox (EPR paradox), Wikipedia https://en.wikipedia.org/wiki/EPR_paradox[10]  Bell's Theorem and Negative Probabilities, David R. Schneider, http://drchinese.com/David/Bell_Theorem_Negative_Probabilities.htm[11] On the Einstein Podolsky Rosen Paradox, John S. Bell, Physics 1964 http://www.drchinese.com/David/Bell_Compact.pdf[13] Testing Bell's Theorem -  CHSH Experiment, James Tankersley, 2020-01-01 https://codeserver.net/bell/chsh, or 2019-11-24 https://sites.google.com/site/physicschecker/references/testing-bell-simulation[14] Code on GitHub https://github.com/tankersleyj/bell[25] Bertlmann's Socks and the Nature of Reality - J.S.Bell - 1980 - https://cds.cern.ch/record/142461/files/198009299.pdf (accessed 2023-02-04)

Enclosures:

Bell mini-conference February 11

Talks (schedule), starting at 16 CET time:

16:00 Marc Fleury, Review of Isolation achieved in the Aspect and Zeilinger experiments.  The case of standing waves (blog)

16:30 Richard Gill, Myths and misunderstandings. Bell’s “Reply to critics” said it all (article)

17:00 Jarek Duda, Boltzmann vs Feynman path ensemble - Born rule and Bell violation in Ising model (article, slides)

17:30 Álvaro García, Correlation and contextuality loopholes are equivalent (article1,article2)

18:00 Robert Close, Geometrical Model of Bell Inequality Violation (slides)
18:30 James Tankersley, Faking Bell (false violations) and Control Testing (simulation, discussion)

19:00 Tim Palmer, Is Superdeterminism really such a ridiculous idea? 
Then discussion focused on the above questions. 

James Tankersley

Faking Bell (false violations) and Control Testing

I will present a graphical computer simulation [1] of Bell CHSH/Eberhart tests, demonstrating how Quantum models [3] violate Bell's inequalities and ideal Classical models do not. I will then show how Classic models can be made to strongly violate Bell’s inequalities through effects such as Malus Loss (loss favoring “intermediate angles” [3] between particle and deflector that are neither equal nor “opposite” [orthogonal or antiparallel]). 


We can then imagine loss-less violations of Bell’s inequalities including Rotation of particle polarity or spin toward Bell violating angles.


Finally I will propose control tests with pre-polarized particles to detect false violations of Bell due to known or unknown effects. Control tests involve emitting each new particle 1 with a randomly selected polarity or spin angle, and emit pair particle 2 with polarity or spin angle opposite of particle 1. Control tests should not violate Bell. [2] 


Physical experiments that claim to violate Bell’s inequalities with entangled (quantum) particles should also perform control tests with pre-polarized (classical) particles that do not violate Bell, confirming that the experiment is not producing false violations.


[1] Testing Bell (CHSH/Eberhart Proofs & False Violations) James Tankersley Jr https://codeserver.net/bell/chsh (accessed Feb 5, 2023)

[2] Testing Bell (False Violations & the Case for Control Tests) James Tankersley Jr https://sites.google.com/site/physicschecker/unsettled-physics/testing-bells-theorem-paper (accessed Feb 5, 2023)

[3] Bertlmann’s Socks and the Nature of Reality, J.S. Bell, 1980, https://cds.cern.ch/record/142461/files/198009299.pdf
[4] Control Testing Bell’s Inequalities James Tankersley Jr https://sites.google.com/site/physicschecker/unsettled-physics/control-testing-bell-inequalities (accessed Feb 9, 2023)

James Tankersley answers

(draft article: https://sites.google.com/site/physicschecker/unsettled-physics/testing-bells-theorem-paper)

To paraphrase J.S. Bell in “Bertlmann’s Socks” [1], the classic model only exactly replicates the quantum model when classic (spin) angle happens to randomly be exactly correlated or anti-correlated with the deflector angle, but not at other “intermediate angles”.


Quantum particles collapse to polarity or spin angle that is the same or “opposite” as a deflector (particle 1 collapses to the same, orthogonal or antiparallel angle as deflector 1 and particle 2 collapses to opposite of particle 1). 


Classical particles are emitted with random polarity or spin angle with no correlation to a deflector (particle 1 is emitted with a randomly selected angle and particle 2 is emitted with angle opposite of particle 1).


The key difference is that each new classical particle “mirror image” pair is emitted set to one of any possible set of polarization or spin angles (with each particle opposite of each other), while quantum entangled particle pairs can only ever have one of a tiny set of possible polarization or spin angles (same, orthogonal or antiparallel of a deflector), with each particle opposite of each other. [1]  A mathematical difference that can be measured.


[1] Bertlmann’s Socks and the Nature of Reality. J.S. Bell 1980 https://cds.cern.ch/record/142461/files/198009299.pdf