Decomposable and atomic projection maps
Operator Algebras
2009-04-02 v1
Abstract
It is shown that a trace invariant projection map, i.e. a positive unital idempotent map, of a finite dimensional C*-algebra into itself is non-decomposable if and only if it is atomic, or equivalently not the sum of a 2-positive and a 2-copositive map. In particular projections onto spin factors of dimension greater than 6 are atomic.
Cite
@article{arxiv.0904.0103,
title = {Decomposable and atomic projection maps},
author = {Erling Stormer},
journal= {arXiv preprint arXiv:0904.0103},
year = {2009}
}
Comments
7 pages