Wigner-PDC description of photon entanglement as a local-realistic theory

TL;DR

This paper demonstrates that the Wigner-PDC model of photon entanglement can be interpreted as a local-realistic theory consistent with quantum predictions, offering new insights into Bell experiments and loophole issues.

Contribution

It reinterprets the Wigner-PDC formalism as a local-realistic model without contradicting quantum mechanics, providing a new perspective on Bell tests and detector efficiencies.

Findings

Wigner-PDC can be viewed as a local-realistic formalism.

The approach explains the loophole-free Bell test challenges.

Provides a simple interpretation of the subtraction of ZPF intensity.

Abstract

Regardless of past proposals (already disproved in experimental work by Brida et al), the Wigner picture of Parametric Down Conversion (works by Casado et al) can be interpreted as a local-realistic formalism, without the need to depart from quantum mechanical predictions at any step, at least for the relevant subset of QED-states. This involves reinterpreting the expressions for the detection probabilities, by means of an additional mathematical manipulation; though such manipulation seemingly provides enough freedom to guarantee consistency with the expectable, experimentally testable behavior of detectors, this is, in any case, irrelevant in relation to our main result, of a purely mathematical nature. Besides, the Wigner-PDC approach opens clear room to explain the elusive nature of a loop-hole free proof of the incompatibility of nature with that local-realism, without the need to assume hypothetical technological inefficiencies yet to overcome after several decades of experimental work. In relation to this, we also address the consequences of this framework in relation to typical Bell experiments. Additionally, we also propose an extremely simple interpretation on that apparently awkward "subtraction" of the average ZPF intensity at the Wigner image of the detection process.