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arXiv · 1407.8233

Violations of Bell inequalities from random pure states

Max R. Atkin·Stefan Zohren
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Abstract

We consider the expected violations of Bell inequalities from random pure states. More precisely, we focus on a slightly generalised version of the CGLMP inequality, which concerns Bell experiments of two parties, two measurement options and N outcomes and analyse their expected quantum violations from random pure states for varying N, assuming the conjectured optimal measurement operators. It is seen that for small N the Bell inequality is not violated on average, while for larger N it is. Both ensembles of unstructured as well as structured random pure states are considered. Using techniques from random matrix theory this is obtained analytically for small and large N and numerically for intermediate N. The results show a beautiful interplay of different aspects of random matrix theory, ranging from the Marchenko-Pastur distribution and fixed-trace ensembles to the O(n) model.

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Max R. Atkin, Stefan Zohren. 2015-06-03. Violations of Bell inequalities from random pure states. https://doi.org/10.1103/physreva.92.012331

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