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arXiv · 1704.05421

The Hadamard Determinant Inequality - Extensions to Operators on a Hilbert Space

Soumyashant Nayak
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Abstract

A generalization of classical determinant inequalities like Hadamard's inequality and Fischer's inequality is studied. For a version of the inequalities originally proved by Arveson for positive operators in von Neumann algebras with a tracial state, we give a different proof. We also improve and generalize to the setting of finite von Neumann algebras, some `Fischer-type' inequalities by Matic for determinants of perturbed positive-definite matrices. In the process, a conceptual framework is established for viewing these inequalities as manifestations of Jensen's inequality in conjunction with the theory of operator monotone and operator convex functions on $[0,\infty)$. We place emphasis on documenting necessary and sufficient conditions for equality to hold.

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BibTeXRIS

Soumyashant Nayak. 2017-04-18. The Hadamard Determinant Inequality - Extensions to Operators on a Hilbert Space. https://doi.org/10.1016/j.jfa.2017.10.009

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