The spectra of subnormal operators
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- by C. R. Putnam PDF
- Proc. Amer. Math. Soc. 28 (1971), 473-477 Request permission
Abstract:
It is shown that a subnormal operator having its spectrum on a simple closed curve is necessarily normal, and that the corresponding assertion with “subnormal” replaced by “hyponormal” is in general false.References
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Additional Information
- © Copyright 1971 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 28 (1971), 473-477
- MSC: Primary 47.40
- DOI: https://doi.org/10.1090/S0002-9939-1971-0275215-8
- MathSciNet review: 0275215