English

Numerical radius inequalities involving commutators of $G_{1}$ operators

Functional Analysis 2017-09-07 v1 Operator Algebras

Abstract

We prove numerical radius inequalities involving commutators of G1G_{1} operators and certain analytic functions. Among other inequalities, it is shown that if AA and XX are bounded linear operators on a complex Hilbert space, then \begin{equation*} w(f(A)X+X\bar{f}(A))\leq {\frac{2}{d_{A}^{2}}}w(X-AXA^{\ast }), \end{equation*} where AA is a G1G_{1} operator with σ(A)D\sigma (A)\subset \mathbb{D} and ff is analytic on the unit disk D\mathbb{D} such that Re(f)>0\textrm{{Re}}(f)>0 and f(0)=1f(0)=1.

Keywords

Cite

@article{arxiv.1709.01850,
  title  = {Numerical radius inequalities involving commutators of $G_{1}$ operators},
  author = {Mojtaba Bakherad and Fuad Kittaneh},
  journal= {arXiv preprint arXiv:1709.01850},
  year   = {2017}
}

Comments

10 pages, Complex Analysis and Operator Theory Journal 2017