English

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

Quantum Physics 2014-03-05 v1 Operator Algebras

Abstract

Convex sets of completely positive maps and positive semidefinite kernels are considered in the most general context of modules over CC^*-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.

Keywords

Cite

@article{arxiv.1202.5905,
  title  = {Completely positive maps on modules, instruments, extremality problems, and applications to physics},
  author = {Juha-Pekka Pellonpää},
  journal= {arXiv preprint arXiv:1202.5905},
  year   = {2014}
}

Comments

32 pages

R2 v1 2026-06-21T20:25:33.785Z