HYPONORMAL TOEPLITZ OPERATORS ON THE BERGMAN SPACE

• Lee, Jong-Rak (Department of Mathematics, Sungkyunkwan University) ;
• Lee, You-Ho (Department of Internet Information, Daegu Haany University)
• 투고 : 2007.11.08
• 발행 : 2008.03.25

초록

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

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