Further inequalities for the numerical radius of off-diagonal part of 2 by 2 operator matrices

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Published: Feb 25, 2025
DOI: https://doi.org/10.5556/j.tkjm.56.2025.5435
Keywords:
Numerical radius positive operator operator norm

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Mehdi Naimi
Université de Mostaganem Abdelhamid Ibn Badis
https://orcid.org/0000-0001-8405-2251
Mohammed Benharrat
Ecole Nationale Polytechnique d'Oran-Maurice Audin (Ex. ENSET d'Oran)

Abstract

In this paper, using a refinement of the classical Young inequality, we present some new upper weighted bounds for the numerical radius of $2\times 2$ block matrices, with entries are bounded operators.

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How to Cite
Naimi, M., & Benharrat, M. (2025). Further inequalities for the numerical radius of off-diagonal part of 2 by 2 operator matrices. Tamkang Journal of Mathematics. https://doi.org/10.5556/j.tkjm.56.2025.5435
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Online First
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Papers
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This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.

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