(Nonrelativistic) Quantum Bit Commitment Really Is Impossible
نویسنده
چکیده
Unconditionally secure (nonrelativistic) quantum bit commitment has been shown to be impossible by Mayers [23] and Lo and Chau [19, 20], but the claim is repeatedly challenged. The bit commitment theorem is reviewed here and the central conceptual point, that an ‘Einstein-Podolsky-Rosen’ attack or cheating strategy can always be applied, is clarified. The question of whether following such a cheating strategy can ever be disadvantageous to the cheater is considered and answered in the negative. PACS numbers: 03.67.-a, 03.67.Dd, 89.70.+c
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