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arXiv · 2008.10840

Improvement of $A$-numerical radius inequalities of semi-Hilbertian space operators

Pintu Bhunia·Raj Kumar Nayak·Kallol Paul
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Abstract

Let $\mathcal{H}$ be a complex Hilbert space and let $A$ be a positive operator on $\mathcal{H}$. We obtain new bounds for the $A$-numerical radius of operators in semi-Hilbertian space $\mathcal{B}_A(\mathcal{H})$ that generalize and improve on the existing ones. Further, we estimate bounds for the $B$-operator seminorm and $B$-numerical radius of $2\times 2$ operator matrices, where $B=\mbox{diag}(A,A)$. The bounds obtained here improve on the existing ones.

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Pintu Bhunia, Raj Kumar Nayak, Kallol Paul. 2020-08-25. Improvement of $A$-numerical radius inequalities of semi-Hilbertian space operators. https://doi.org/10.1007/s00025-021-01439-w

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