dorsal/arxiv
View SchemaA classical analogue of negative information
| Authors | Jonathan Oppenheim, Robert W. Spekkens, Andreas Winter |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0511247 |
| URL | https://arxiv.org/abs/quant-ph/0511247 |
Abstract
Recently, it was discovered that the `quantum partial information' needed to merge one party's state with another party's state is given by the conditional entropy, which can be negative [Horodecki, Oppenheim, and Winter, Nature 436, 673 (2005)]. Here we find a classical analogue of this, based on a long known relationship between entanglement and shared private correlations: namely, we consider a private distribution held between two parties, and correlated to a reference system, and ask how much secret communication is needed for one party to send her distribution to the other. We give optimal protocols for this task, and find that private information can be negative - the sender's distribution can be transferred and the potential to send future distributions in secret is gained through the distillation of a secret key. An analogue of `quantum state exchange' is also discussed and one finds cases where exchanging a distribution costs less than for one party to send it. The results give new classical protocols, and also clarify the various relationships between entanglement and privacy.
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"abstract": "Recently, it was discovered that the `quantum partial information\u0027 needed to\nmerge one party\u0027s state with another party\u0027s state is given by the conditional\nentropy, which can be negative [Horodecki, Oppenheim, and Winter, Nature 436,\n673 (2005)]. Here we find a classical analogue of this, based on a long known\nrelationship between entanglement and shared private correlations: namely, we\nconsider a private distribution held between two parties, and correlated to a\nreference system, and ask how much secret communication is needed for one party\nto send her distribution to the other. We give optimal protocols for this task,\nand find that private information can be negative - the sender\u0027s distribution\ncan be transferred and the potential to send future distributions in secret is\ngained through the distillation of a secret key. An analogue of `quantum state\nexchange\u0027 is also discussed and one finds cases where exchanging a distribution\ncosts less than for one party to send it. The results give new classical\nprotocols, and also clarify the various relationships between entanglement and\nprivacy.",
"arxiv_id": "quant-ph/0511247",
"authors": [
"Jonathan Oppenheim",
"Robert W. Spekkens",
"Andreas Winter"
],
"categories": [
"quant-ph"
],
"title": "A classical analogue of negative information",
"url": "https://arxiv.org/abs/quant-ph/0511247"
},
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