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arXiv · 2105.09381

No Bipartite-Nonlocal Causal Theory Can Explain Nature's Correlations

Xavier Coiteux-Roy·Elie Wolfe·Marc-Olivier Renou
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Abstract

We show that some tripartite quantum correlations are inexplicable by any causal theory involving bipartite nonclassical common causes and unlimited shared randomness. This constitutes a device-independent proof that Nature's nonlocality is fundamentally at least tripartite in every conceivable physical theory - no matter how exotic. To formalize this claim we are compelled to substitute Svetlichny's historical definition of genuine tripartite nonlocality with a novel theory-agnostic definition tied to the framework of Local Operations and Shared Randomness (LOSR). A companion article [PRA. 104, 052207 (2021)] generalizes these concepts to any number of parties, providing experimentally amenable device-independent inequality constraints along with quantum correlations violating them, thereby certifying that Nature's nonlocality must be boundlessly multipartite.

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Xavier Coiteux-Roy, Elie Wolfe, Marc-Olivier Renou. 2021-11-11. No Bipartite-Nonlocal Causal Theory Can Explain Nature's Correlations. https://doi.org/10.1103/physrevlett.127.200401

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