dorsal/arxiv
View SchemaCounterexample to an additivity conjecture for output purity of quantum channels
| Authors | R. F. Werner, A. S. Holevo |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0203003 |
| URL | https://arxiv.org/abs/quant-ph/0203003 |
| DOI | 10.1063/1.1498491 |
Abstract
A conjecture arising naturally in the investigation of additivity of classical information capacity of quantum channels states that the maximal purity of outputs from a quantum channel, as measured by the p-norm, should be multiplicative with respect to the tensor product of channels. We disprove this conjecture for p>4.79. The same example (with p=infinity) also disproves a conjecture for the multiplicativity of the injective norm of Hilbert space tensor products.
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"abstract": "A conjecture arising naturally in the investigation of additivity of\nclassical information capacity of quantum channels states that the maximal\npurity of outputs from a quantum channel, as measured by the p-norm, should be\nmultiplicative with respect to the tensor product of channels. We disprove this\nconjecture for p\u003e4.79. The same example (with p=infinity) also disproves a\nconjecture for the multiplicativity of the injective norm of Hilbert space\ntensor products.",
"arxiv_id": "quant-ph/0203003",
"authors": [
"R. F. Werner",
"A. S. Holevo"
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"doi": "10.1063/1.1498491",
"title": "Counterexample to an additivity conjecture for output purity of quantum channels",
"url": "https://arxiv.org/abs/quant-ph/0203003"
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