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Implications of Superstrong Nonlocality for Cryptography

Harry Buhrman·Matthias Christandl·Falk Unger·Stephanie Wehner·Andreas Winter
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Abstract

Non-local boxes are hypothetical ``machines'' that give rise to superstrong non-local correlations, leading to a stronger violation of Bell/CHSH inequalities than is possible within the framework of quantum mechanics. We show how non-local boxes can be used to perform any two-party secure computation. We first construct a protocol for bit commitment and then show how to achieve oblivious transfer using non-local boxes. Both have been shown to be impossible using quantum mechanics alone.

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Harry Buhrman, Matthias Christandl, Falk Unger, Stephanie Wehner, Andreas Winter. 2006-06-29. Implications of Superstrong Nonlocality for Cryptography. https://doi.org/10.1098/rspa.2006.1663

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