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arXiv · 2007.08654

Numerical radii of accretive matrices

Yassine Bedrani·Fuad Kittaneh·Mohammed Sababheh
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Abstract

The numerical radius of a matrix is a scalar quantity that has many applications in the study of matrix analysis. Due to the difficulty in computing the numerical radius, inequalities bounding it have received a considerable attention in the literature. In this article, we present many new bounds for the numerical radius of accretive matrices. The importance of this study is the presence of a new approach that treats a specific class of matrices, namely the accretive ones. The new bounds provide a new set of inequalities, some of which can be considered as refinements of other existing ones, while others present new insight to some known results for positive matrices.

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Yassine Bedrani, Fuad Kittaneh, Mohammed Sababheh. 2020-07-16. Numerical radii of accretive matrices. https://arxiv.org/abs/2007.08654

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