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arXiv · 2210.10729

Ruminations on Matrix Convexity and the Strong Subadditivity of Quantum Entropy

Michael Aizenman·Giorgio Cipolloni
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Abstract

The familiar second derivative test for convexity, combined with resolvent calculus, is shown to yield a useful tool for the study of convex matrix-valued functions. We demonstrate the applicability of this approach on a number of theorems in this field. These include convexity principles which play an essential role in the Lieb-Ruskai proof of the strong subadditivity of quantum entropy.

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Michael Aizenman, Giorgio Cipolloni. 2022-10-19. Ruminations on Matrix Convexity and the Strong Subadditivity of Quantum Entropy. https://doi.org/10.1007/s11005-023-01638-2

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