Weighted numerical radius inequalities for operator and operator matrices

被引:0
作者
Raj Kumar Nayak
机构
[1] Ghani Khan Choudhury Institute of Engineering and Technology (GKCIET),Department of Mathematics
来源
Acta Scientiarum Mathematicarum | 2024年 / 90卷
关键词
Numerical radius; Norm inequality; Primary 47A12; 47A30; Secondary 47A63; 15A60;
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摘要
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 2×2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$2 \times 2$$\end{document} 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, T~\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\tilde{T}}$$\end{document} of an operator T∈B(H),\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$T \in {\mathcal {B}}({\mathcal {H}}),$$\end{document} where T~=|T|1/2U|T|1/2,\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\tilde{T}} = |T|^{1/2} U |T|^{1/2},$$\end{document} and T=U|T|\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$T = U |T|$$\end{document} is the Canonical Polar decomposition of T.
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页码:193 / 206
页数:13
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