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Multipartite Nonlocal Quantum Correlations Resistant to Imperfections

H. Buhrman·P. Hoyer·S. Massar·H. Roehrig
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Abstract

We use techniques for lower bounds on communication to derive necessary conditions in terms of detector efficiency or amount of super-luminal communication for being able to reproduce with classical local hidden-variable theories the quantum correlations occurring in EPR-type experiments in the presence of noise. We apply our method to an example involving n parties sharing a GHZ-type state on which they carry out measurements and show that for local-hidden variable theories, the amount of super-luminal classical communication c and the detector efficiency eta are constrained by eta 2^(-c/n) = O(n^(-1/6)) even for constant general error probability epsilon = O(1).

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H. Buhrman, P. Hoyer, S. Massar, H. Roehrig. 2004-10-19. Multipartite Nonlocal Quantum Correlations Resistant to Imperfections. https://doi.org/10.1103/physreva.73.012321

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