dorsal/arxiv
View SchemaCoin Tossing is Strictly Weaker Than Bit Commitment
| Authors | Adrian Kent |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/9810067 |
| URL | https://arxiv.org/abs/quant-ph/9810067 |
| DOI | 10.1103/PhysRevLett.83.5382 |
| Journal | Phys.Rev.Lett. 83 (1999) 5382-5384 |
Abstract
We define cryptographic assumptions applicable to two mistrustful parties who each control two or more separate secure sites between which special relativity guarantees a time lapse in communication. We show that, under these assumptions, unconditionally secure coin tossing can be carried out by exchanges of classical information. We show also, following Mayers, Lo and Chau, that unconditionally secure bit commitment cannot be carried out by finitely many exchanges of classical or quantum information. Finally we show that, under standard cryptographic assumptions, coin tossing is strictly weaker than bit commitment. That is, no secure classical or quantum bit commitment protocol can be built from a finite number of invocations of a secure coin tossing black box together with finitely many additional information exchanges.
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"abstract": "We define cryptographic assumptions applicable to two mistrustful parties who\neach control two or more separate secure sites between which special relativity\nguarantees a time lapse in communication. We show that, under these\nassumptions, unconditionally secure coin tossing can be carried out by\nexchanges of classical information. We show also, following Mayers, Lo and\nChau, that unconditionally secure bit commitment cannot be carried out by\nfinitely many exchanges of classical or quantum information. Finally we show\nthat, under standard cryptographic assumptions, coin tossing is strictly weaker\nthan bit commitment. That is, no secure classical or quantum bit commitment\nprotocol can be built from a finite number of invocations of a secure coin\ntossing black box together with finitely many additional information exchanges.",
"arxiv_id": "quant-ph/9810067",
"authors": [
"Adrian Kent"
],
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"quant-ph",
"cs.CR"
],
"doi": "10.1103/PhysRevLett.83.5382",
"journal_ref": "Phys.Rev.Lett. 83 (1999) 5382-5384",
"title": "Coin Tossing is Strictly Weaker Than Bit Commitment",
"url": "https://arxiv.org/abs/quant-ph/9810067"
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