Obtaining a contradiction between local realism and quantum mechanics using only one correlation function

TL;DR

This paper demonstrates a contradiction between local realism and quantum mechanics using only a single correlation function from measurements on entangled spin-1/2 particles, without relying on Bell inequalities.

Contribution

It introduces a novel approach to challenge local realism by deriving contradictions solely from a single correlation function, bypassing traditional Bell inequality frameworks.

Findings

Contradiction between local realism and quantum mechanics established

Single correlation function suffices to reveal the contradiction

No Bell inequalities needed for the argument

Abstract

An ensemble consisting on systems of two entangled spin 1/2 particles, all of them in the same global quantum state, are considered. The two spins are measured, each of them, on a fixed direction, at two randomly selected measurement times. Realism, plus locality and freedom of choice referred to these chosen times, are assumed. Then, from the sole correlation function related to the two measurements, without considering any Bell inequalities, a contradiction between these assumptions and quantum mechanics is found.