dorsal/arxiv
View SchemaVariable Bias Coin Tossing
| Authors | Roger Colbeck, Adrian Kent |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0508149 |
| URL | https://arxiv.org/abs/quant-ph/0508149 |
| DOI | 10.1103/PhysRevA.73.032320 |
| Journal | Phys. Rev. A 73, 032320 (2006) |
Abstract
Alice is a charismatic quantum cryptographer who believes her parties are unmissable; Bob is a (relatively) glamorous string theorist who believes he is an indispensable guest. To prevent possibly traumatic collisions of self-perception and reality, their social code requires that decisions about invitation or acceptance be made via a cryptographically secure variable bias coin toss (VBCT). This generates a shared random bit by the toss of a coin whose bias is secretly chosen, within a stipulated range, by one of the parties; the other party learns only the random bit. Thus one party can secretly influence the outcome, while both can save face by blaming any negative decisions on bad luck. We describe here some cryptographic VBCT protocols whose security is guaranteed by quantum theory and the impossibility of superluminal signalling, setting our results in the context of a general discussion of secure two-party computation. We also briefly discuss other cryptographic applications of VBCT.
{
"annotation_id": "d866ff7d-dc66-4354-b935-8a9f860238e9",
"date_created": "2026-03-02T18:02:20.776000Z",
"date_modified": "2026-03-02T18:02:20.776000Z",
"file_hash": "e88479b1d6a41ddc64fbcd4897bb60ec84439ffef5d6a5d7d1fe101460cbc2fa",
"private": false,
"record": {
"abstract": "Alice is a charismatic quantum cryptographer who believes her parties are\nunmissable; Bob is a (relatively) glamorous string theorist who believes he is\nan indispensable guest. To prevent possibly traumatic collisions of\nself-perception and reality, their social code requires that decisions about\ninvitation or acceptance be made via a cryptographically secure variable bias\ncoin toss (VBCT). This generates a shared random bit by the toss of a coin\nwhose bias is secretly chosen, within a stipulated range, by one of the\nparties; the other party learns only the random bit. Thus one party can\nsecretly influence the outcome, while both can save face by blaming any\nnegative decisions on bad luck.\n We describe here some cryptographic VBCT protocols whose security is\nguaranteed by quantum theory and the impossibility of superluminal signalling,\nsetting our results in the context of a general discussion of secure two-party\ncomputation. We also briefly discuss other cryptographic applications of VBCT.",
"arxiv_id": "quant-ph/0508149",
"authors": [
"Roger Colbeck",
"Adrian Kent"
],
"categories": [
"quant-ph",
"cs.CR"
],
"doi": "10.1103/PhysRevA.73.032320",
"journal_ref": "Phys. Rev. A 73, 032320 (2006)",
"title": "Variable Bias Coin Tossing",
"url": "https://arxiv.org/abs/quant-ph/0508149"
},
"schema_id": "dorsal/arxiv",
"source": {
"execution_id": "93c85d78-bd42-48c5-8cae-14676451eeaf",
"id": "arXiv Dataset IDs",
"type": "Model",
"variant": "snapshot-2026-03-01",
"version": "0.1.0"
},
"user_id": 1000002
}