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arXiv · 1902.08655

On the essential spectrum of $\lambda$-Toeplitz operators over compact Abelian groups

A. R. Mirotin
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Abstract

In the recent paper by Mark C. Ho (2014) the notion of a $\lambda$-Toeplitz operator on the Hardy space $H^2(\mathbb{T})$ over the one-dimensional torus $\mathbb{T}$ was introduced and it was shown (under the supplementary condition) that for $\lambda\in \mathbb{T}$ the essential spectrum of such an operator is invariant with respect to the rotation $z\mapsto \lambda z$; if in addition $\lambda$ is not of finite order the essential spectrum is circular. In this paper, we generalize these results to the case when $\mathbb{T}$ is replaced by an arbitrary compact Abelian group whose dual is totally ordered.

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A. R. Mirotin. 2019-02-22. On the essential spectrum of $\lambda$-Toeplitz operators over compact Abelian groups. https://arxiv.org/abs/1902.08655

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