Abstract
A two-point algebra is a set of bounded analytic functions on the unit disk that agree at two distinct points \(a,b \in \mathbb {D}\). This algebra serves as a multiplier algebra for the family of Hardy Hilbert spaces \(H^2_t := \{ f\in H^2 : f(a)=tf(b)\}\), where \(t\in \mathbb {C}\cup \{\infty \}\). We show that various spectra of certain Toeplitz operators acting on these spaces are connected.
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The authors thank John McCarthy and Scott McCullough for helpful discussion, as well as the reviewer for their thoughtful suggestions.
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The first named author was supported in part by NSF Grant DMS-1565243. Notice: This manuscript has been authored, in part, by UT-Battelle, LLC, under contract DE-AC05-00OR22725 with the US Department of Energy (DOE). The US government retains and the publisher, by accepting the article for publication, acknowledges that the US government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this manuscript, or allow others to do so, for US government purposes. DOE will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan (http://energy.gov/downloads/doe-public-access-plan).
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Felder, C., Pfeffer, D.T. & Russo, B.P. Spectra for Toeplitz Operators Associated with a Constrained Subalgebra. Integr. Equ. Oper. Theory 94, 24 (2022). https://doi.org/10.1007/s00020-022-02700-9
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DOI: https://doi.org/10.1007/s00020-022-02700-9