A New Necessary Condition for the Hyponormality of Toeplitz Operators on the Bergman Space

Zeljko Cuckovic, Raul E. Curto

A well known result of C. Cowen states that, for a symbol $\phi \in L^{\infty },\phi \equiv \bar{f}+g(f,g\in H^2)$, the Toeplitz operator $T_{\phi }$ acting on the Hardy space of th…