Weighted numerical radius inequalities for operator and operator matrices

Abstract

The concept of weighted numerical radius has been defined recently. In this article, we obtain several upper bounds for the weighted numerical radius of operators and \(2 \times 2\) operator matrices which generalize and improve some well-known famous inequalities for the classical numerical radius. The article also derives an upper bound for the weighted numerical radius of the Aluthge transformation, \({\tilde{T}}\) of an operator \(T \in {\mathcal {B}}({\mathcal {H}}),\) where \({\tilde{T}} = |T|^{1/2} U |T|^{1/2},\) and \(T = U |T|\) is the Canonical Polar decomposition of T.