Indecomposable compact perturbations of the bilateral shift
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- by Domingo A. Herrero PDF
- Proc. Amer. Math. Soc. 62 (1977), 254-258 Request permission
Abstract:
Recent results of M. Radjabalipour and H. Radjavi assert that the sum of a normal operator N with spectrum on a smooth Jordan curve and a compact operator K in the Macaev ideal ${\mathfrak {S}_\omega }$ is decomposable provided the spectrum of $N + K$ does not fill the interior of the curve. Examples are given to show that this result cannot be essentially improved by taking K in a larger ideal.References
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Additional Information
- © Copyright 1977 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 62 (1977), 254-258
- MSC: Primary 47B37; Secondary 47A65
- DOI: https://doi.org/10.1090/S0002-9939-1977-0435922-6
- MathSciNet review: 0435922