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Local Hidden Variable Theories for Quantum States

Barbara M. Terhal·Andrew C. Doherty·David Schwab
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Abstract

While all bipartite pure entangled states violate some Bell inequality, the relationship between entanglement and non-locality for mixed quantum states is not well understood. We introduce a simple and efficient algorithmic approach for the problem of constructing local hidden variable theories for quantum states. The method is based on constructing a so-called symmetric quasi-extension of the quantum state that gives rise to a local hidden variable model with a certain number of settings for the observers Alice and Bob.

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Barbara M. Terhal, Andrew C. Doherty, David Schwab. 2002-10-15. Local Hidden Variable Theories for Quantum States. https://doi.org/10.1103/physrevlett.90.157903

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