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引用次数: 0
摘要
加权数值半径的概念是最近定义的。在这篇文章中,我们得到了算子和 \(2 \times 2\) 算子矩阵的加权数值半径的几个上界,它们概括并改进了经典数值半径的一些著名不等式。文章还推导了算子 \(T \in {\mathcal {B}}({\mathcal {H}}),\) 的 Aluthge 变换、\({\tilde{T}}\) 的加权数值半径的上界,其中 \({\tilde{T}} = |T|^{1/2} U |T|^{1/2},\) 和 \(T = U |T|) 是 T 的 Canonical Polar 分解。
Weighted numerical radius inequalities for operator and operator matrices
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.