$a$-Weyl’s theorem for operator matrices
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- by Young Min Han and Slaviša V. Djordjević PDF
- Proc. Amer. Math. Soc. 130 (2002), 715-722 Request permission
Abstract:
If $M_{C}=\left (\begin {smallmatrix}A&C0&B\end {smallmatrix}\right )$ is a $2\times 2$ upper triangular matrix on the Hilbert space $H\oplus K$, then $a$-Weyl’s theorem for $A$ and $B$ need not imply $a$-Weyl’s theorem for $M_{C}$, even when $C=0$. In this note we explore how $a$-Weyl’s theorem and $a$-Browder’s theorem survive for $2\times 2$ operator matrices on the Hilbert space.References
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Additional Information
- Young Min Han
- Affiliation: Department of Mathematics, Sungkyunkwan University, Suwon 440-746, Korea
- Address at time of publication: Department of Mathematics, 14 MacLean Hall, University of Iowa, Iowa City, Iowa 52242-1419
- Email: ymhan@math.skku.ac.kr, yhan@math.uiowa.edu
- Slaviša V. Djordjević
- Affiliation: Department of Mathematics, Faculty of Philosophy, University of Niš, Ćirila and Metodija 2, 18000 Niš, Yugoslavia
- Email: slavdj@archimed.filfak.ni.ac.yu
- Received by editor(s): February 29, 2000
- Received by editor(s) in revised form: August 25, 2000
- Published electronically: July 31, 2001
- Additional Notes: This work was supported by the Brain Korea 21 Project (through Seoul National University)
- Communicated by: Joseph A. Ball
- © Copyright 2001 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 130 (2002), 715-722
- MSC (2000): Primary 47A50, 47A53
- DOI: https://doi.org/10.1090/S0002-9939-01-06110-X
- MathSciNet review: 1866025