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A note on quantum entropy inequalities and channel capacities

Heng Fan
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Abstract

Quantum entropy inequalities are studied. Some quantum entropy inequalities are obtained by several methods. For entanglement breaking channel, we show that the entanglement-assisted classical capacity is upper bounded by $\log d$. A relationship between entanglement-assisted and one-shot unassisted capacities is obtained. This relationship shows the entanglement-assisted channel capacity is upper bounded by the sum of $\log d$ and the one-shot unassisted classical capacity.

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Heng Fan. 2002-12-25. A note on quantum entropy inequalities and channel capacities. https://doi.org/10.1088/0305-4470/36/48/010

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