On some EPR (Einstein, Podolsky, Rosen) issues

TL;DR

This paper critically reexamines the EPR argument, removing philosophical assumptions, and discusses how hidden variables theories and quantum non-locality relate to experimental tests with entangled photons.

Contribution

It demonstrates that the EPR argument can be reformulated without philosophical elements and clarifies the assumptions behind hidden variables theories and quantum non-locality.

Findings

EPR argument can be developed without 'element of physical reality'

Hidden variables theories rely on assumptions that are experimentally testable

Quantum non-locality is linked to hypotheses about pre-measurement properties of entangled photons

Abstract

A critical reconsideration of the EPR (Einstein-Podolsky-Rosen) paper shows that the EPR argument can be developed without using the concept of `element of physical reality', thus eliminating any philosophical element in the logical chains of the paper. Deprived of its philosophical ornament, the EPR argument plainly reduces to require what quantum mechanics can not do: to assign definite values to two incompatible physical quantities. Hidden variables theories built up according to Bell - type theorems are formulated on the basis of the assumption that the locality condition implies the statistical independence between two measurements space - like separated. This assumption is valid only with the additional one that statistical dependence between two measurements requires a causal connection between them. This additional assumption rules out the possibility that statistical dependence may due to an intrinsic property of the physical system under study. Therefore, hidden variables theories are built up with a restriction which leads them to be disproved by experiment. Quantum mechanical non - locality, invoked for describing EPR - type experiments, is strictly connected to the hypothesis (NDV hypothesis) according to which the twin photons of entangled pairs do not have a definite polarization before measurements. Both hypotheses are used only for describing EPR experiments and not for making predictions. Therefore, they can be dropped without reducing the predictive power of quantum mechanics concerning entangled photons pairs. Furthermore, both hypotheses can be experimentally tested by a modification of a standard experimental apparatus designed for studying entangled photons pairs.