## Annals of Functional Analysis

### Perspectives and completely positive maps

Frank Hansen

#### Abstract

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

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

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

https://projecteuclid.org/euclid.afa/1484363068

Digital Object Identifier
doi:10.1215/20088752-3784269

Subjects
Primary: 47A63: Operator inequalities

#### Citation

Hansen, Frank. Perspectives and completely positive maps. Ann. Funct. Anal. 8 (2017), no. 2, 168--176. doi:10.1215/20088752-3784269. https://projecteuclid.org/euclid.afa/1484363068

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