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The physics of no-bit-commitment : Generalized quantum non-locality versus oblivious transfer

Tony Short·Nicolas Gisin·Sandu Popescu
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Abstract

We show here that the recent work of Wolf and Wullschleger (quant-ph/0502030) on oblivious transfer apparently opens the possibility that non-local correlations which are stronger than those in quantum mechanics could be used for bit-commitment. This is surprising, because it is the very existence of non-local correlations which in quantum mechanics prevents bit-commitment. We resolve this apparent paradox by stressing the difference between non-local correlations and oblivious transfer, based on the time-ordering of their inputs and outputs, which prevents bit-commitment.

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Tony Short, Nicolas Gisin, Sandu Popescu. 2005-04-18. The physics of no-bit-commitment : Generalized quantum non-locality versus oblivious transfer. https://arxiv.org/abs/quant-ph/0504134

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