Hyponormal Toeplitz operators on the Bergman space. II.

摘要

In this paper we consider the hyponormality of Toeplitz operators $T_{arphi}$ on the Bergman space $L_a^2(mathbb D)$ with symbol in the case of function $f+ overline{g}$ with polynomials $f$ and $g$. We present some necessary conditions for the hyponormality of $T_arphi$ under certain assumptions about the coefficients of $arphi$.