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arXiv · 1405.5173

Spectra of Some Weighted Composition Operators on $H^2$

Carl Cowen·Eungil Ko·Derek Thompson·Feng Tian
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Abstract

We completely characterize the spectrum of a weighted composition operator $W_{\psi, \varphi}$ on $H^{2}(\mathbb{D})$ when $\varphi$ has Denjoy-Wolff point $a$ with $0<|\varphi '(a)|< 1$, the iterates, $\varphi_{n}$, converge uniformly to $a$, and $\psi$ is in $H^{\infty}(\mathbb{D})$ and continuous at $a$. We also give bounds and some computations when $|a|=1$ and $\varphi '(a)=1$ and, in addition, show that these symbols include all linear fractional $\varphi$ that are hyperbolic and parabolic non-automorphisms. Finally, we use these results to eliminate possible weights $\psi$ so that $W_{\psi, \varphi}$ is seminormal.

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Carl Cowen, Eungil Ko, Derek Thompson, Feng Tian. 2014-05-20. Spectra of Some Weighted Composition Operators on $H^2$. https://doi.org/10.14232/actasm-014-542-y

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