Further inequalities for the numerical radii of Hilbert space operators

Subject Areas : Operator theory

M. Hosseini ¹ , R. Nuraei ² , M. Shahhosseini ^{3 *} , M. R. Sorouhesh ⁴

1 - Department of Mathematics, South Tehran Branch, Islamic Azad University, Tehran, Iran
2 - Department of Mathematics, South Tehran Branch, Islamic Azad University, Tehran, Iran
3 - Department of Mathematics, Shahr-e-Qods Branch, Islamic Azad University, Tehran, Iran
4 - Department of Mathematics, South Tehran Branch, Islamic Azad University, Tehran, Iran

Received: 2024-11-25 Accepted : 2025-01-23 Published : 2025-03-01

Keywords: Numerical radii, norm, inequality,

Abstract :

This paper studies numerical radius inequalities in Hilbert space operators. We obtain some bounds for the accretive dissipative matrices, extending and improving earlier bounds. We also give results concerning block matrices.

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