Further inequalities for the numerical radii of Hilbert space operators

محورهای موضوعی : 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

تاریخ دریافت : 1403/09/05 تاریخ پذیرش : 1403/11/04 تاریخ انتشار : 1403/12/11

کلید واژه: Numerical radii, norm, inequality,

چکیده مقاله :

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.

چکیده انگلیسی:

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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