Rocky Mountain Journal of Mathematics

Upper and lower bounds for the numerical radius with an application to involution operators

Amer Abu-Omar and Fuad Kittaneh

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New upper and lower bounds for the numerical radii of Hilbert space operators are given. An application to involution operators is also provided.

Article information

Rocky Mountain J. Math., Volume 45, Number 4 (2015), 1055-1064.

First available in Project Euclid: 2 November 2015

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Mathematical Reviews number (MathSciNet)

Zentralblatt MATH identifier

Primary: 47A10: Spectrum, resolvent 47A12: Numerical range, numerical radius 47A30: Norms (inequalities, more than one norm, etc.) 47A63: Operator inequalities 47B15: Hermitian and normal operators (spectral measures, functional calculus, etc.)

Numerical radius operator norm inequality involution operator


Abu-Omar, Amer; Kittaneh, Fuad. Upper and lower bounds for the numerical radius with an application to involution operators. Rocky Mountain J. Math. 45 (2015), no. 4, 1055--1064. doi:10.1216/RMJ-2015-45-4-1055.

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