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arXiv · 1503.06165

Essentially Normal Composition Operators on $H^2$

Mor Katz
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Abstract

We prove a simple criterion for essential normality of composition operators on the Hardy space induced by maps in a reasonably large class of analytic self-maps of the unit disk. By combining this criterion with boundary Carathéodory-Fejér interpolation theory, we exhibit a parametrization for all rational self-maps of the unit disk which induce essentially normal composition operators.

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Mor Katz. 2015-03-20. Essentially Normal Composition Operators on $H^2$. https://arxiv.org/abs/1503.06165

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