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arXiv · 2004.09955

Inequalities for the generalized numerical radius

H. Abbas·S. Harb·H. Issa
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Abstract

In the present paper, we provide several inequalities for the generalized numerical radius of operator matrices as introduced by A. Abu-omar and F. Kittaneh in [3]. We generalize the convexity and the log-convexity results obtained by M. Sababheh in [12] for the case of the numerical radius to the case of the generalized numerical radius. We illustrate our work by providing a positive answer for the question addressed in [12] for the convexity of a certain matrix operator function. Moreover, and motivated by the results of A. Aldalabih and F. Kittaneh in [2] for the case of Hilbert-Schmidt numerical radius norm, we use some Schatten $p$-norm inequalities for partitioned $2\times 2$ block-matrices to provide several Schatten $p$-norm numerical radius inequalities.

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H. Abbas, S. Harb, H. Issa. 2020-04-21. Inequalities for the generalized numerical radius. https://arxiv.org/abs/2004.09955

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