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A quantum protocol for cheat-sensitive weak coin flipping

R. W. Spekkens·Terry Rudolph
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Abstract

We present a quantum protocol for the task of weak coin flipping. We find that, for one choice of parameters in the protocol, the maximum probability of a dishonest party winning the coin flip if the other party is honest is 1/sqrt(2). We also show that if parties restrict themselves to strategies wherein they cannot be caught cheating, their maximum probability of winning can be even smaller. As such, the protocol offers additional security in the form of cheat sensitivity.

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R. W. Spekkens, Terry Rudolph. 2002-11-13. A quantum protocol for cheat-sensitive weak coin flipping. https://doi.org/10.1103/physrevlett.89.227901

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