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arXiv · 2201.12753

Test of Genuine Multipartite Nonlocality

Ya-Li Mao·Zheng-Da Li·Sixia Yu·Jingyun Fan
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Abstract

While Bell nonlocality of a bipartite system is counter-intuitive, multipartite nonlocality in our many-body world turns out to be even more so. Recent theoretical study reveals in a theory-agnostic manner that genuine multipartite nonlocal correlations cannot be explained by any causal theory involving fewer-partite nonclassical resources and global shared randomness. Here we provide a Bell-type inequality as a test for genuine multipartite nonlocality in network by exploiting a matrix representation of the causal structure of a multipartite system. We further present experimental demonstrations that both four-photon GHZ state and generalized four-photon GHZ state significantly violate the inequality, i.e., the observed four-partite correlations resist explanations involving three-way nonlocal resources subject to local operations and common shared randomenss, hence confirming that nature is boundless multipartite nonlocal.

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Ya-Li Mao, Zheng-Da Li, Sixia Yu, Jingyun Fan. 2022-01-30. Test of Genuine Multipartite Nonlocality. https://doi.org/10.1103/physrevlett.129.150401

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