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arXiv · 0905.3419

Strong no-go theorem for Gaussian quantum bit commitment

Loïck Magnin·Frédéric Magniez·Anthony Leverrier·Nicolas J. Cerf
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Abstract

Unconditionally secure bit commitment is forbidden by quantum mechanics. We extend this no-go theorem to continuous-variable protocols where both players are restricted to use Gaussian states and operations, which is a reasonable assumption in current-state optical implementations. Our Gaussian no-go theorem also provides a natural counter-example to a conjecture that quantum mechanics can be rederived from the assumption that key distribution is allowed while bit commitment is forbidden in Nature.

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Loïck Magnin, Frédéric Magniez, Anthony Leverrier, Nicolas J. Cerf. 2010-01-06. Strong no-go theorem for Gaussian quantum bit commitment. https://doi.org/10.1103/physreva.81.010302

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