Proceedings of the American Mathematical Society

Author(s): Takahiko Nakazi
Journal: Proc. Amer. Math. Soc. 136 (2008), 2425-2428.
MSC (2000): Primary 47B20, 47B35
Posted: 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.

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Retrieve articles in Proceedings of the American Mathematical Society with MSC (2000): 47B20, 47B35

Takahiko Nakazi
Affiliation: Department of Mathematics, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan

DOI: 10.1090/S0002-9939-08-08752-2
PII: S 0002-9939(08)08752-2
Keywords: Trigonometric Toeplitz operators, hyponormal operator, Pick problem
Received by editor(s): December 2, 2005,
Received by editor(s) in revised form: April 12, 2006
Posted: 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 of article: Copyright 2008, American Mathematical Society

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