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arXiv · 2402.06279

Spectra of infinite Cayley graphs, examples with pure band spectra

Pierre de la Harpe
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Abstract

It is shown that there are groups $Γ$ with finite generating sets $S$ such that the adjacency operator of the Cayley graph ${\rm Cay}(Γ,S)$ is a disjoint union of $N$ intervals, for arbitrarily large integers $N$.

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Pierre de la Harpe. 2024-02-09. Spectra of infinite Cayley graphs, examples with pure band spectra. https://arxiv.org/abs/2402.06279

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