Hyponormal Toeplitz operators and zeros of polynomials
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- by Takahiko Nakazi
- Proc. Amer. Math. Soc. 136 (2008), 2425-2428
- DOI: https://doi.org/10.1090/S0002-9939-08-08752-2
- Published electronically: March 7, 2008
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Abstract:
The problem of hyponormality for Toeplitz operators with (trigo- nometric) polynomial symbols is studied. We give a necessary and sufficient condition using the zeros of the analytic polynomial induced by the Fourier coefficients of the symbol.References
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Bibliographic Information
- Takahiko Nakazi
- Affiliation: Department of Mathematics, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan
- Received by editor(s): December 2, 2005
- Received by editor(s) in revised form: April 12, 2006
- Published electronically: March 7, 2008
- Additional Notes: This research was partially supported by Grant-in-Aid for Scientific Research, Japan Society for the Promotion of Science.
- Communicated by: Joseph A. Ball
- © Copyright 2008 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 136 (2008), 2425-2428
- MSC (2000): Primary 47B20, 47B35
- DOI: https://doi.org/10.1090/S0002-9939-08-08752-2
- MathSciNet review: 2390509