# Convexity of a certain operator trace functional

@inproceedings{Evert2021ConvexityOA, title={Convexity of a certain operator trace functional}, author={Eric Evert and Scott A. McCullough and Tea vStrekelj and Anna Vershynina}, year={2021} }

In this article the operator trace function Λr,s(A)[K,M ] := tr(K ∗ArMArK)s is introduced and its convexity and concavity properties are investigated. This function has a direct connection to several well-studied operator trace functions that appear in quantum information theory, in particular when studying data processing inequalities of various relative entropies. In the paper the interplay between Λr,s and the well-known operator functions Γp,s and Ψp,q,s is used to study the stability of…

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