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arXiv · 2502.19470

Three-Body Non-Locality in Particle Decays

Paweł Horodecki·Kazuki Sakurai·Abhyoudai S. Shaleena·Michael Spannowsky
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Abstract

The exploration of entanglement and Bell non-locality among multi-particle quantum systems offers a profound avenue for testing and understanding the limits of quantum mechanics and local real hidden variable theories. In this work, we examine non-local correlations among three massless spin-1/2 particles generated from the three-body decay of a massive particle, utilizing a framework based on general four-fermion interactions. By analyzing several inequalities, we address the detection of deviations from quantum mechanics as well as violations of two key hidden variable theories: fully local-real and bipartite local-real theories. Our approach encompasses the standard Mermin inequality and the tight $4 \times 4 \times 2$ inequality, providing a comprehensive framework for probing three-partite non-local correlations. Our findings provide deeper insights into the boundaries of classical and quantum theories in three-particle systems, advancing the understanding of non-locality in particle decays and its relevance to particle physics and quantum foundations.

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Paweł Horodecki, Kazuki Sakurai, Abhyoudai S. Shaleena, Michael Spannowsky. 2025-02-26. Three-Body Non-Locality in Particle Decays. https://doi.org/10.1007/jhep10(2025)160

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