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Ruminations on Matrix Convexity and the Strong Subadditivity of Quantum Entropy

Quantum Physics 2024-07-26 v5 Statistical Mechanics Information Theory Mathematical Physics math.IT math.MP

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.

Keywords

Cite

@article{arxiv.2210.10729,
  title  = {Ruminations on Matrix Convexity and the Strong Subadditivity of Quantum Entropy},
  author = {Michael Aizenman and Giorgio Cipolloni},
  journal= {arXiv preprint arXiv:2210.10729},
  year   = {2024}
}

Comments

The published version of this paper includes a local mistake in Eq. (5.7). Posted here are: i) the corresponding Erratum & Addendum (LMP 2024), and ii) a corrected version of the paper with the minor adjustments spelled in (i)