English

A matrix subadditivity inequality for f(A+B) and f(A)+f(B)

Functional Analysis 2007-05-23 v1 Operator Algebras

Abstract

Let f be a non-negative concave function on the positive half-line. Let A and B be two positive matrices. Then, for all symmetric norms, || f(A+B) || is less than || f(A)+f(B) ||. When f is operator concave, this was proved by Ando and Zhan. Our method is simpler. Several related results are presented.

Keywords

Cite

@article{arxiv.math/0702475,
  title  = {A matrix subadditivity inequality for f(A+B) and f(A)+f(B)},
  author = {Jean-Christophe Bourin and Mitsuru Uchiyama},
  journal= {arXiv preprint arXiv:math/0702475},
  year   = {2007}
}

Comments

accepted in LAA