Further inequalities for the numerical radii of Hilbert space operators

الموضوعات :

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

تاريخ الإرسال : 23 الإثنين , جمادى الأولى, 1446 تاريخ التأكيد : 23 الخميس , رجب, 1446 تاريخ الإصدار : 01 السبت , رمضان, 1446

الکلمات المفتاحية: Numerical radii, norm, inequality,

ملخص المقالة :

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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