A note on the spectral area of Toeplitz operators

Chu, Cheng; Khavinson, Dmitry

doi:10.1090/proc/12900

A note on the spectral area of Toeplitz operators
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by Cheng Chu and Dmitry Khavinson

Proc. Amer. Math. Soc. 144 (2016), 2533-2537

DOI: https://doi.org/10.1090/proc/12900

Published electronically: October 20, 2015

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Abstract:

In this note, we show that for hyponormal Toeplitz operators, there exists a lower bound for the area of the spectrum. This extends the known estimate for the spectral area of Toeplitz operators with an analytic symbol.

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