Banach Journal of Mathematical Analysis

Total decomposition and block numerical range

Abbas Salemi

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Abstract

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

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

Dates
First available in Project Euclid: 14 August 2011

Permanent link to this document
https://projecteuclid.org/euclid.bjma/1313362979

Digital Object Identifier
doi:10.15352/bjma/1313362979

Mathematical Reviews number (MathSciNet)
MR2738519

Zentralblatt MATH identifier
1219.47014

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

Keywords
block numerical range total decomposition spectrum

Citation

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


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References

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