Strong nogo theorem for Gaussian quantum bit commitment
Abstract
Unconditionally secure bit commitment is forbidden by quantum mechanics. We extend this nogo theorem to continuousvariable protocols where both players are restricted to use Gaussian states and operations, which is a reasonable assumption in currentstate optical implementations. Our Gaussian nogo theorem also provides a natural counterexample to a conjecture that quantum mechanics can be rederived from the assumption that key distribution is allowed while bit commitment is forbidden in Nature.
 Publication:

Physical Review A
 Pub Date:
 January 2010
 DOI:
 10.1103/PhysRevA.81.010302
 arXiv:
 arXiv:0905.3419
 Bibcode:
 2010PhRvA..81a0302M
 Keywords:

 03.67.Dd;
 Quantum cryptography;
 Quantum Physics
 EPrint:
 4 pages. v2: We discuss the implications of this theorem on the BrassardFuchs conjecture and the CBH theorem