Quasinormal and Hyponormal Weighted Composition Operators on \(H^2\) and \(A^2_{\alpha }\) with Linear Fractional Compositional Symbol
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Abstract
In this paper, we study quasinormal and hyponormal composition operators \(W_{\psi ,\varphi }\) with linear fractional compositional symbol \(\varphi \) on the Hardy and weighted Bergman spaces. We characterize the quasinormal composition operators induced on \(H^{2}\) and \(A_{\alpha }^{2}\) by these maps and many such weighted composition operators, showing that they are necessarily normal in all known cases. We eliminate several possibilities for hyponormal weighted composition operators but also give new examples of hyponormal weighted composition operators on \(H^2\) which are not quasinormal.
Keywords
Weighted composition operator Composition operator Hyponormal QuasinormalMathematics Subject Classification
47B33References
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