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arXiv · 0811.1649

The non-locality of n noisy Popescu-Rohrlich boxes

Matthias Fitzi·Esther Hänggi·Valerio Scarani·Stefan Wolf
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Abstract

We quantify the amount of non-locality contained in n noisy versions of so-called Popescu-Rohrlich boxes (PRBs), i.e., bipartite systems violating the CHSH Bell inequality maximally. Following the approach by Elitzur, Popescu, and Rohrlich, we measure the amount of non-locality of a system by representing it as a convex combination of a local behaviour, with maximal possible weight, and a non-signalling system. We show that the local part of n systems, each of which approximates a PRB with probability $1-\epsilon$, is of order $\Theta(\epsilon^{\lceil n/2\rceil})$ in the isotropic, and equal to $(3\epsilon)^n$ in the maximally biased case.

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Matthias Fitzi, Esther Hänggi, Valerio Scarani, Stefan Wolf. 2008-11-11. The non-locality of n noisy Popescu-Rohrlich boxes. https://doi.org/10.1088/1751-8113/43/46/465305

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