Universally-composable privacy amplification from causality constraints

Lluis Masanes

doi:10.1103/physrevlett.102.140501

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arXiv · 0807.2158

Universally-composable privacy amplification from causality constraints

Lluis Masanes

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Abstract

We consider schemes for secret key distribution which use as a resource correlations that violate Bell inequalities. We provide the first security proof for such schemes, according to the strongest notion of security, the so called universally-composable security. Our security proof does not rely on the validity of quantum mechanics, it solely relies on the impossibility of arbitrarily-fast signaling between separate physical systems. This allows for secret communication in situations where the participants distrust their quantum devices.

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quant-ph cs.CR cs.IT math.IT

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Lluis Masanes. 2009-05-19. Universally-composable privacy amplification from causality constraints. https://doi.org/10.1103/physrevlett.102.140501

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