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arXiv · 0903.2715

Quantifying multipartite nonlocality

Jean-Daniel Bancal·Cyril Branciard·Nicolas Gisin·Stefano Pironio
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Abstract

The nonlocal correlations of multipartite entangled states can be reproduced by a classical model if sufficiently many parties join together or if sufficiently many parties broadcast their measurement inputs. The maximal number m of groups and the minimal number k of broadcasting parties that allow for the reproduction of a given set of correlations quantify their multipartite nonlocal content. We show how upper-bounds on m and lower-bounds on k can be computed from the violation of the Mermin-Svetlichny inequalities. While n-partite GHZ states violate these inequalities maximally, we find that W states violate them only by a very small amount.

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Jean-Daniel Bancal, Cyril Branciard, Nicolas Gisin, Stefano Pironio. 2009-08-27. Quantifying multipartite nonlocality. https://doi.org/10.1103/physrevlett.103.090503

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