dorsal/arxiv
View SchemaQuantum state merging and negative information
| Authors | Michal Horodecki, Jonathan Oppenheim, Andreas Winter |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0512247 |
| URL | https://arxiv.org/abs/quant-ph/0512247 |
| DOI | 10.1007/s00220-006-0118-x |
| Journal | Comm. Math. Phys. 269, 107 (2007) |
Abstract
We consider a quantum state shared between many distant locations, and define a quantum information processing primitive, state merging, that optimally merges the state into one location. As announced in [Horodecki, Oppenheim, Winter, Nature 436, 673 (2005)], the optimal entanglement cost of this task is the conditional entropy if classical communication is free. Since this quantity can be negative, and the state merging rate measures partial quantum information, we find that quantum information can be negative. The classical communication rate also has a minimum rate: a certain quantum mutual information. State merging enabled one to solve a number of open problems: distributed quantum data compression, quantum coding with side information at the decoder and sender, multi-party entanglement of assistance, and the capacity of the quantum multiple access channel. It also provides an operational proof of strong subadditivity. Here, we give precise definitions and prove these results rigorously.
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"abstract": "We consider a quantum state shared between many distant locations, and define\na quantum information processing primitive, state merging, that optimally\nmerges the state into one location. As announced in [Horodecki, Oppenheim,\nWinter, Nature 436, 673 (2005)], the optimal entanglement cost of this task is\nthe conditional entropy if classical communication is free. Since this quantity\ncan be negative, and the state merging rate measures partial quantum\ninformation, we find that quantum information can be negative. The classical\ncommunication rate also has a minimum rate: a certain quantum mutual\ninformation. State merging enabled one to solve a number of open problems:\ndistributed quantum data compression, quantum coding with side information at\nthe decoder and sender, multi-party entanglement of assistance, and the\ncapacity of the quantum multiple access channel. It also provides an\noperational proof of strong subadditivity. Here, we give precise definitions\nand prove these results rigorously.",
"arxiv_id": "quant-ph/0512247",
"authors": [
"Michal Horodecki",
"Jonathan Oppenheim",
"Andreas Winter"
],
"categories": [
"quant-ph"
],
"doi": "10.1007/s00220-006-0118-x",
"journal_ref": "Comm. Math. Phys. 269, 107 (2007)",
"title": "Quantum state merging and negative information",
"url": "https://arxiv.org/abs/quant-ph/0512247"
},
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