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arXiv · 2001.04522

$A$-Numerical radius orthogonality and parallelism of semi-Hilbertian space operators and their applications

Pintu Bhunia·Kais Feki·Kallol Paul
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Abstract

In this paper, we aim to introduce and characterize the concept of numerical radius orthogonality of operators on a complex Hilbert space $\mathcal{H}$ which are bounded with respect to the semi-norm induced by a positive operator $A$ on $\mathcal{H}$. Moreover, a characterization of the $A$-numerical radius parallelism for $A$-rank one operators is proved. As applications of the obtained results, we obtain some $\mathbb{A}$-numerical radius inequalities of operator matrices where $\mathbb{A}$ is the operator diagonal matrix with diagonal entries are positive operator $A$. Some other related results are also investigated.

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Pintu Bhunia, Kais Feki, Kallol Paul. 2020-01-13. $A$-Numerical radius orthogonality and parallelism of semi-Hilbertian space operators and their applications. https://doi.org/10.1007/s41980-020-00392-8

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