Testing the EPR Locality using B-Mesons

TL;DR

This paper explores the potential for testing local realistic theories using Bell inequalities with entangled B-mesons, highlighting current experimental limitations and the need for improved decay time resolution.

Contribution

It demonstrates the theoretical possibility of testing certain local realistic theories with B-mesons despite experimental challenges.

Findings

Test is feasible for a restricted class of LRT

Current KEKB setup cannot perform the test due to decay time indeterminacy

Resolving decay time indeterminacy is crucial for future tests

Abstract

We study the possibility of testing local realistic theory (LRT), envisioned implicitly by Einstein, Podolsky and Rosen in 1935, based on the Bell inequality for the correlations in the decay modes of entangled K or B-mesons. It is shown that such a test is possible for a restricted class of LRT, despite the passive nature of decay events and/or the non-unitary treatment of the correlations which invalidate the test for general LRT. Unfortunately, the present setup of the KEKB (Belle) experiment, where the coherence of entangled B-mesons has been confirmed recently, does not admit such a test due to the inability of determining the decay times of the entangled pairs separately. The indeterminacy also poses a problem for ensuring the locality of the test, indicating that improvement to resolve the indeterminacy is crucial for the test of LRT.