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Operator monotone functions of several variables

Frank Hansen
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Abstract

We propose a notion of operator monotonicity for functions of several variables, which extends the well known notion of operator monotonicity for functions of only one variable. The notion is chosen such that a fundamental relationship between operator convexity and operator monotonicity for functions of one variable is extended also to functions of several variables.

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Frank Hansen. 2002-05-14. Operator monotone functions of several variables. https://arxiv.org/abs/math/0205147

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