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arXiv · 1507.00239

Arbitrarily long relativistic bit commitment

Kaushik Chakraborty·André Chailloux·Anthony Leverrier
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Abstract

We consider the recent relativistic bit commitment protocol introduced by Lunghi et al. [Phys. Rev. Lett. 2015] and present a new security analysis against classical attacks. In particular, while the initial complexity of the protocol scaled double-exponentially with the commitment time, our analysis shows that the correct dependence is only linear. This has dramatic implications in terms of implementation: in particular, the commitment time can easily be made arbitrarily long, by only requiring both parties to communicate classically and perform efficient classical computation.

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Kaushik Chakraborty, André Chailloux, Anthony Leverrier. 2015-07-01. Arbitrarily long relativistic bit commitment. https://doi.org/10.1103/physrevlett.115.250501

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