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arXiv · 1202.5905

Completely positive maps on modules, instruments, extremality problems, and applications to physics

Juha-Pekka Pellonpää
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Abstract

Convex sets of completely positive maps and positive semidefinite kernels are considered in the most general context of modules over $C^*$-algebras and a complete charaterization of their extreme points is obtained. As a byproduct, we determine extreme quantum instruments, preparations, channels, and extreme autocorrelation functions. Various applications to quantum information and measurement theories are given. The structure of quantum instruments is analyzed thoroughly.

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Juha-Pekka Pellonpää. 2012-02-27. Completely positive maps on modules, instruments, extremality problems, and applications to physics. https://doi.org/10.1088/1751-8113/46/2/025303

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