Hyponormal Toeplitz operators and zeros of polynomials

Nakazi, Takahiko

doi:10.1090/S0002-9939-08-08752-2

Hyponormal Toeplitz operators and zeros of polynomials
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by Takahiko Nakazi PDF

Proc. Amer. Math. Soc. 136 (2008), 2425-2428 Request permission

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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