Still more on norms of completely positive maps
Quantum Physics
2010-09-14 v2 Functional Analysis
Abstract
King and Ruskai asked whether the norm of a completely positive map acting between Schatten classes of operators is equal to that of its restriction to the real subspace of self-adjoint operators. Proofs have been promptly supplied by Watrous and Audenaert. Here we provide one more proof, in fact of a slightly more general fact, under the (slightly weaker) assumption of 2-positivity. The argument is elementary and self-contained.
Keywords
Cite
@article{arxiv.quant-ph/0603110,
title = {Still more on norms of completely positive maps},
author = {Stanislaw J. Szarek},
journal= {arXiv preprint arXiv:quant-ph/0603110},
year = {2010}
}
Comments
2 pages; changes (all minor) in v.2: references, notation, added comments