Banach Journal of Mathematical Analysis

Total decomposition and block numerical range

Abbas Salemi

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Let $\mathcal{H}$ be a separable Hilbert space and let $\mathcal{A} \in \mathcal{B}(\mathcal{H})$. In this note the notion of a total decomposition is introduced, and it is shown that sometimes the block numerical ranges corresponding to a total decomposition approximate $\sigma(A),$ sometimes not.

Article information

Banach J. Math. Anal., Volume 5, Number 1 (2011), 51-55.

First available in Project Euclid: 14 August 2011

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Mathematical Reviews number (MathSciNet)

Zentralblatt MATH identifier

Primary: 47A12: Numerical range, numerical radius
Secondary: 49M27: Decomposition methods

block numerical range total decomposition spectrum


Salemi, Abbas. Total decomposition and block numerical range. Banach J. Math. Anal. 5 (2011), no. 1, 51--55. doi:10.15352/bjma/1313362979.

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