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A Re-examination of Bell's Inequality: Polarization Correspondence in Entangled Photon Pairs

Jingyuan Guo

Published Aug 18, 2026• 0 citations
Publisher

Abstract

Bell's inequality is widely regarded as the death knell of local hidden variable theories. However, this paper points out that Bell's argument implicitly relies on an overly narrow assumption about what constitutes a "local hidden variable"—namely, that hidden variables must assign measurement outcomes to each particle independently at the moment of measurement. This paper proposes that the deterministic correspondence established between entangled particles at the moment of their creation, and determined by initial conditions, can itself serve as a local hidden variable. As long as the polarization direction of the photons is not altered, this correspondence persists indefinitely. It is independent of whether a measurement is performed, and requires no superluminal communication to sustain. From this perspective, quantum entanglement experiments do not violate special relativity; the violation of Bell's inequality merely rules out a specific class of hidden variable models, not all forms of local realism.

DOI
10.5281/zenodo.21983265

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Bell's inequality is widely regarded as the death knell of local hidden variable theories. However, this paper points out that Bell's argument implicitly relies on an overly narrow assumption about what constitutes a "local hidden variable"—namely, that hidden variables must assign measurement outcomes to each particle independently at the moment of measurement. This paper proposes that the deterministic correspondence established between entangled particles at the moment of their creation, and determined by initial conditions, can itself serve as a local hidden variable. As long as the polarization direction of the photons is not altered, this correspondence persists indefinitely. It is independent of whether a measurement is performed, and requires no superluminal communication to sustain. From this perspective, quantum entanglement experiments do not violate special relativity; the violation of Bell's inequality merely rules out a specific class of hidden variable models, not all forms of local realism.
Conventional tests of Bell’s inequality rely on entangled photon pairs. Here, we replace entangled pairs with two independent photons of orthogonal polarization, and demonstrate that Bell’s inequality is still violated. Given the inherent local realism of independent photons, this experiment proves that Bell’s inequality cannot falsify the local realism of photons. We thus conjecture that the violation of Bell’s inequality by entangled photon pairs originates from their orthogonal polarizations, rather than the breakdown of local realism. To interpret this unexpected violation with independent photons, we further substitute the two photons with two monochromatic light beams, and calculate the transmittance correlation through polarizers via Malus’s law and Karl Pearson’s correlation formula. We show that this correlation also defies Bell’s inequality. Retracing the derivation of Bell’s inequality reveals its validity is restricted to binary events, which accounts for the observed violation with light beams. Finally, we propose a thought experiment involving gradual attenuation of light intensity down to the single-photon regime, and hypothesize that single-photon transmission through a polarizer does not constitute a binary event. This hypothesis provides a unified interpretation for both our experimental findings and all canonical Bell inequality tests reported to date.
The Bell inequality constrains the outcomes of measurements on pairs of distant entangled particles. The Bell contradiction states that the Bell inequality is inconsistent with the calculated outcomes of these quantum experiments. This contradiction led many to question the underlying assumptions, viz. so-called realism and locality. The probability model underlying the Bell inequality is generally left implicit. We propose an explicit probability model for the CHSH version of the Bell experiment. This model has only two simultaneously observable detector settings per measurement, and therefore does not assume realism. The quantum expectation now becomes a conditional expectation, given the two detector settings. This probability model is in full agreement with both quantum mechanics and experiments. As a result, the model satisfies the Bell inequality; there are no so-called violations. We extend this model to include a hidden variable. This extended model is not Bell-separable. This non-separability implies that the model is non-deterministic or non-local (or both).
EPR showed that two particles emitted from a source can be entangled by a shared wavefunction where two non-commuting observables (position, momentum) can be simultaneously real, leading to a contradiction with quantum mechanics (two non-commuting variables can not be simultaneously real). John Bell derived an inequality where any local hidden variables prediction is bounded and quantum mechanics can violate the inequality. Bell tests on correlated photon pairs showed a clear violation of the Bell inequality and agreement with quantum mechanics. This study revealed that the Bell inequality holds at any individual instances in a given system but it does not hold over the entire population. The Bell inequality is not an incompatibility criterion for local hidden variables vs quantum mechanics rather it is a criterion for an individual nature vs population dynamics. The nonlocality prediction given by wavefunction is a system approximation and local causality (photon polarization) provides a complete description of the Bell tests. The paper concludes with great satisfaction that the measurement of two correlated photons at a distance was a local cause (photon-filter interaction did not violate the special theory of relativity).
ABSTRACT This work presents a revised analysis and corresponding perspective of Bell‐type inequalities and their connection to entanglement in polarization experiments with single‐photon resolution. It is argued that standard derivations of Bell‐type inequalities implicitly rely on additional assumptions beyond those originally stated, specifically concerning the cardinalities of the sets of measurements and the sets of photon‐pair properties (Einstein's elements of physical reality, Bell's ). Any model‐based averages must depend on these cardinalities and violations of Bell‐type inequalities become possible for certain ranges of them. In addition, we argue that for Aspect‐type experiments, the statistical properties associated with Bell's (hidden variable) λ can be different before and after actual photon‐transmission through the polarizers. This distinction is particularly necessary for the actual equipment used in the Aspect‐type experiments. Building on these observations, we construct a model based on a consistent evaluation of the measurement events relative to each other. The model reproduces all quantum‐mechanical expectation values for polarization correlations without invoking instantaneous influences at a distance, and additionally yields explicit outcomes for individual photon‐pair measurements. Within this framework, our Einstein‐type Global Space‐Time Model (GSTM) accounts also for polarization correlations in Malus‐type experiments and addresses all commonly discussed paradoxes associated with single‐photon measurements.
Bell-state experiments with pairs of polarization-entangled photons are interpreted without any hinge on non-local mechanisms. The presented model rests on a careful analysis of published experimental findings. These foundations are implemented into a standard quantum mechanical treatment that obeys the purely local nature of each polarization preparation in the course of a measurement process. Polarization entanglement is ascribed to the generation of indiscernible photon pairs while undistorted propagation maintains this interrelation. Thus, the proposed approach assigns the essential characteristics of polarization entanglement to each constituent of an entangled pair. Accordingly, space-time separated polarization preparations lead to consistent probabilities of joint detection events. The obtained results agree with those of previous non-local models and thus reproduce the experimentally required violations of the Bell inequality. Since the presented approach lacks any non-local phenomenon, hidden variables are rendered superfluous, too.
Abstract We propose a novel class of local deterministic models to explain the correlations observed in entangled singlet quantum states. In these models, hidden variables influence both the entangled pair preparation and the measurement settings, thereby relaxing the measurement independence assumption used in Bell’s theorem. Our model accurately reproduces the expected quantum results and demonstrates that freely chosen measurement settings do not necessarily preclude the possibility of hidden variables inducing correlations between the settings and outcomes. This approach reveals an intricate relationship between local determinism and quantum mechanics, showing that local hidden variable theories can be consistent with the predictions of quantum theory. This result calls into question the conventional interpretation, based on Bell’s inequalities, that local theories are fundamentally incompatible with quantum mechanics.