Hyponormality of Toeplitz operators on the Bergman space of an annulus
Sadraoui, Mohammed Guediri and Houcine . 2020
Abstract. A bounded operator S on a Hilbert space is hyponormal if S*S-SS* is positive. In this work we find necessary conditions for the hyponormality of the Toeplitz operaor T_f+g^- on the Bergman space of the annulus 1/2 < |z|< 1, where f and g are analytic, and f satisfies a smoothness condition.
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