Examples of nonnormal seminormal operators whose spectra are not spectral sets
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- by Kevin F. Clancey
- Proc. Amer. Math. Soc. 24 (1970), 797-800
- DOI: https://doi.org/10.1090/S0002-9939-1970-0254643-X
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Abstract:
An example is given of a nonnormal seminormal operator on a Hilbert space whose spectrum is thin (in the sense of von Neumann) and is therefore not a spectral set. It is shown that every nonnormal subnormal operator is the limit of a sequence of hyponormal and nonsubnormal operators.References
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Bibliographic Information
- © Copyright 1970 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 24 (1970), 797-800
- MSC: Primary 47.40
- DOI: https://doi.org/10.1090/S0002-9939-1970-0254643-X
- MathSciNet review: 0254643