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arXiv · 1805.09569

An Alternative Estimate for the Numerical Radius of Hilbert Space Operators

M. Shah Hosseini·B. Moosavi·H. R. Moradi
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Abstract

We give an alternative lower bound for the numerical radii of Hilbert space operators. As a by-product, we find conditions such that \begin{equation*} \omega\left(\left[\begin{array}{cc} 0 & R \\ S & 0 \end{array}\right]\right)=\frac{\Vert R \Vert +\Vert S\Vert }{2} \end{equation*} where $R, S \in \mathbb{B}(\mathcal{H})$.

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M. Shah Hosseini, B. Moosavi, H. R. Moradi. 2018-05-24. An Alternative Estimate for the Numerical Radius of Hilbert Space Operators. https://arxiv.org/abs/1805.09569

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