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arXiv · 2405.08939

Exploring the Local Landscape in the Triangle Network

Elisa Bäumer·Victor Gitton·Tamás Kriváchy·Nicolas Gisin·Renato Renner
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Abstract

Characterizing the set of distributions that can be realized in the triangle network is a notoriously difficult problem. In this work, we investigate inner approximations of the set of local (classical) distributions of the triangle network. A quantum distribution that appears to be nonlocal is the Elegant Joint Measurement (EJM) [Entropy. 2019; 21(3):325], which motivates us to study distributions having the same symmetries as the EJM. We compare analytical and neural-network-based inner approximations and find a remarkable agreement between the two methods. Using neural network tools, we also conjecture network Bell inequalities that give a trade-off between the levels of correlation and symmetry that a local distribution may feature. Our results considerably strengthen the conjecture that the EJM is nonlocal.

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Elisa Bäumer, Victor Gitton, Tamás Kriváchy, Nicolas Gisin, Renato Renner. 2024-05-14. Exploring the Local Landscape in the Triangle Network. https://doi.org/10.1103/physreva.111.052453

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