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arXiv · 1908.11182

On inequalities for A-numerical radius of operators

Pintu Bhunia·Kallol Paul·Raj Kumar Nayak
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Abstract

Let $A$ be a positive operator on a complex Hilbert space $\mathcal{H}.$ We present inequalities concerning upper and lower bounds for $A$-numerical radius of operators, which improve on and generalize the existing ones, studied recently in [A. Zamani, A-Numerical radius inequalities for semi-Hilbertian space operators, Linear Algebra Appl. 578 (2019) 159-183]. We also obtain some inequalities for $B$-numerical radius of $2\times 2$ operator matrices where $B$ is the $2\times 2$ diagonal operator matrix whose diagonal entries are $A$. Further we obtain upper bounds for $A$-numerical radius for product of operators which improve on the existing bounds.

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Pintu Bhunia, Kallol Paul, Raj Kumar Nayak. 2019-08-29. On inequalities for A-numerical radius of operators. https://arxiv.org/abs/1908.11182

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