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arXiv · 1911.04222

Variational Representations related to Quantum Rényi Relative Entropies

Guanghua Shi
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Abstract

In this paper, we focus on variational representations of some matrix symmetric norm functions that are related to the quantum Rényi relative entropy. Concretely, we obtain variational representations of the function (A,B)\mapsto \normmm{(B^{q/2}K^*A^pKB^{q/2})^s} for symmetric norms by using the Hölder inequality and Young inequality. These variational expressions enable us to make the proofs of the convexity/concavity of the trace function (A,B)\mapsto \tr (B^{q/2}K^*A^pKB^{q/2})^s more clear.

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Guanghua Shi. 2020-06-19. Variational Representations related to Quantum Rényi Relative Entropies. https://arxiv.org/abs/1911.04222

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