English

Unitarily invariant norm inequalities involving $G_1$ operators

Functional Analysis 2018-01-10 v1 Complex Variables

Abstract

In this paper, we present some upper bounds for unitarily invariant norms inequalities. Among other inequalities, we show some upper bounds for the Hilbert-Schmidt norm. In particular, we prove \begin{align*} \|f(A)Xg(B)\pm g(B)Xf(A)\|_2\leq \left\|\frac{(I+|A|)X(I+|B|)+(I+|B|)X(I+|A|)}{d_Ad_B}\right\|_2, \end{align*} where A,B,XMnA, B, X\in\mathbb{M}_n such that AA, BB are Hermitian with σ(A)σ(B)D\sigma (A)\cup\sigma(B)\subset\mathbb{D} and f,gf, g are analytic on the complex unit disk D\mathbb{{D}}, g(0)=f(0)=1g(0)=f(0)=1, Re(f)>0\textrm{Re}(f)>0 and Re(g)>0\textrm{Re}(g)>0.

Keywords

Cite

@article{arxiv.1801.02934,
  title  = {Unitarily invariant norm inequalities involving $G_1$ operators},
  author = {Mojtaba Bakherad},
  journal= {arXiv preprint arXiv:1801.02934},
  year   = {2018}
}

Comments

To appear in Commun. Korean Math. Society