Annals of Functional Analysis

Perspectives and completely positive maps

Frank Hansen

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We study the filtering of the perspective of a regular operator map of several variables through a completely positive linear map. By this method we are able to extend known operator inequalities of two variables to several variables, with applications in the theory of operator means of several variables. We also extend Lieb and Ruskai’s convexity theorem from two to $n+1$ operator variables for any natural number $n$.

Article information

Ann. Funct. Anal. Volume 8, Number 2 (2017), 168-176.

Received: 8 August 2016
Accepted: 9 August 2016
First available in Project Euclid: 14 January 2017

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Digital Object Identifier

Primary: 47A63: Operator inequalities

partial traces of operator means Lieb and Ruskai’s convexity theorem


Hansen, Frank. Perspectives and completely positive maps. Ann. Funct. Anal. 8 (2017), no. 2, 168--176. doi:10.1215/20088752-3784269.

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