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arXiv · 1710.02473

Monogamy of correlations and entropy inequalities in the Bloch picture

Paul Appel·Marcus Huber·Claude Klöckl
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Abstract

We investigate monogamy of correlations and entropy inequalities in the Bloch representation. Here, both can be understood as direct relations between different correlation tensor elements and thus appear intimately related. To that end we introduce the split Bloch basis, that is particularly useful for representing quantum states with low dimensional support and thus amenable to purification arguments. Furthermore, we find dimension dependent entropy inequalities for the Tsallis 2-entropy. In particular, we present an analogue of the strong subadditivity and a quadratic entropy inequality. These relations are shown to be stronger than subadditivity for finite dimensional cases.

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Paul Appel, Marcus Huber, Claude Klöckl. 2017-10-06. Monogamy of correlations and entropy inequalities in the Bloch picture. https://doi.org/10.1088/2399-6528%2Fab6fb4

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