New Method to Reveal the Conflict Between Local Realism and Quantum Mechanics

TL;DR

This paper introduces the Bell-Zukowski inequality, a new criterion for testing local realism against quantum mechanics in two-particle Bell experiments, linking it to the Bell-Mermin operator and analyzing interference visibility.

Contribution

It formulates the Bell-Zukowski inequality and demonstrates its relation to the Bell-Mermin operator, providing a new method to analyze local realism violations in quantum experiments.

Findings

Bell-Zukowski operator can be represented by the Bell-Mermin operator

Threshold visibility for violation matches theoretical predictions

The inequality offers a new test for local realism in two-particle systems

Abstract

We formulate the expectation value of the Bell-Zukowski operator acting on qubit states of a two-particle Bell experiment. By using the equivalence between a set of N copies of a two-qubit experiment and a standard two-setting Bell experiment in an entangled 2N-particle state, we obtain an inequality, which we may call the Bell-Zukowski inequality. It determines whether the measured correlation functions of two-particle states can be modeled locally and realistically. In this Bell experiment of two particles, the conflict between local realism and quantum mechanics is discussed in conjunction with the violation of the Bell-Zukowski inequality. The main point of the result is that the Bell-Zukowski operator can be represented by the Bell-Mermin operator. The threshold visibility of two-particle interference analyzed in this scheme shows good agreement with the value to cause a violation of the Bell-Zukowski inequality.