dorsal/arxiv
View SchemaAnother Short and Elementary Proof of Strong Subadditivity of Quantum Entropy
| Authors | Mary Beth Ruskai |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0604206 |
| URL | https://arxiv.org/abs/quant-ph/0604206 |
| DOI | 10.1016/S0034-4877(07)00019-5 |
| Journal | Reports on Mathematical Physics 60, 1-12 (2007). |
Abstract
A short and elementary proof of the joint convexity of relative entropy is presented, using nothing beyond linear algebra. The key ingredients are an easily verified integral representation and the strategy used to prove the Cauchy-Schwarz inequality in elementary courses. Several consequences are proved in a way which allow an elementary proof of strong subadditivity in a few more lines. Some expository material on Schwarz inequalities for operators and the Holevo bound for partial measurements is also included.
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"abstract": "A short and elementary proof of the joint convexity of relative entropy is\npresented, using nothing beyond linear algebra. The key ingredients are an\neasily verified integral representation and the strategy used to prove the\n Cauchy-Schwarz inequality in elementary courses. Several consequences are\nproved in a way which allow an elementary proof of strong subadditivity in a\nfew more lines. Some expository material on Schwarz inequalities for operators\nand the Holevo bound for partial measurements is also included.",
"arxiv_id": "quant-ph/0604206",
"authors": [
"Mary Beth Ruskai"
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"doi": "10.1016/S0034-4877(07)00019-5",
"journal_ref": "Reports on Mathematical Physics 60, 1-12 (2007).",
"title": "Another Short and Elementary Proof of Strong Subadditivity of Quantum Entropy",
"url": "https://arxiv.org/abs/quant-ph/0604206"
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