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arXiv · 1910.06775

Some improvements of numerical radius inequalities of operators and operator matrices

Pintu Bhunia·Kallol Paul
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Abstract

We obtain upper bounds for the numerical radius of a product of Hilbert space operators which improve on the existing upper bounds. We generalize the numerical radius inequalities of $n\times n$ operator matrices by using non-negative continuous functions on $[0,\infty)$. We also obtain some upper and lower bounds for the $B$-numerical radius of operator matrices, where $B$ is the diagonal operator matrix whose each diagonal entry is a positive operator $A.$ We show that these bounds generalize and improve on the existing bounds.

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Pintu Bhunia, Kallol Paul. 2019-10-15. Some improvements of numerical radius inequalities of operators and operator matrices. https://doi.org/10.1080/03081087.2020.1781037

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