## Illinois Journal of Mathematics

### Intertwining relations and extended eigenvalues for analytic Toeplitz operators

#### Abstract

We study the intertwining relation $XT_\varphi=T_\psi X$ where $T_\varphi$ and $T_\psi$ are the Toeplitz operators induced on the Hardy space $H^2$ by analytic functions $\varphi$ and $\psi$, bounded on the open unit disc~$\mathbb{U}$, and $X$ is a nonzero bounded linear operator on $H^2$. Our work centers on the connection between intertwining and the image containment $\psi(\mathbb{U})\subset\varphi (\mathbb{U})$, as well as on the nature of the intertwining operator $X$. We use our results to study the extended eigenvalues'' of analytic Toeplitz operators $T_\varphi$, i.e., the special case $XT_{\lambda\varphi}=T_\varphi X$, where $\lambda$ is a complex number.

#### Article information

Source
Illinois J. Math., Volume 52, Number 3 (2008), 1007-1030.

Dates
First available in Project Euclid: 1 October 2009

https://projecteuclid.org/euclid.ijm/1254403728

Digital Object Identifier
doi:10.1215/ijm/1254403728

Mathematical Reviews number (MathSciNet)
MR2546021

Zentralblatt MATH identifier
1174.37003

#### Citation

Bourdon, Paul S.; Shapiro, Joel H. Intertwining relations and extended eigenvalues for analytic Toeplitz operators. Illinois J. Math. 52 (2008), no. 3, 1007--1030. doi:10.1215/ijm/1254403728. https://projecteuclid.org/euclid.ijm/1254403728

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