Surveys in Mathematics and its Applications

ISSN 1842-6298 (electronic), 1843-7265 (print)
 Volume 20 (2025), 1 -- 12

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This work is licensed under a Creative Commons Attribution 4.0 International License.

SOME NUMERICAL RADIUS INEQUALITIES FOR d-TUPLES OF OPERATORS

Messaoud Guesba and Ould Ahmed Mahmoud Sid Ahmed

Abstract. Our aim in this paper is to give new numerical radius inequalities for d-tuples of operators on a complex Hilbert space. We prove several inequalities for multivarible operators on a complex Hilbert space. Based on that some numerical radius inequalities due to Dragomir for a single operator.

2020 Mathematics Subject Classification: 47A05, 47A55, 47B15.
Keywords: Joint numerical radius, joint operator norm, inequalities, normal operator.

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Messaoud Guesba - corresponding author
Faculty of Exact Sciences, Department of Mathematics.
El Oued University, 39000 Algeria.
E-mail: guesbamessaoud2@gmail.com, guesba-messaoud@univ-eloued.dz

Ould Ahmed Mahmoud Sid Ahmed
Mathematics Department, College of Science.
Jouf University Sakaka 2014. Saudi Arabia.
E-mail : sidahmed@ju.edu.sa

https://www.utgjiu.ro/math/sma