Gap Labelling for Almost Periodic Sturm-Liouville Operators

Gerald Teschl; Yifei Wang; Bing Xie; Zhe Zhou

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arXiv · 2601.18312

Gap Labelling for Almost Periodic Sturm-Liouville Operators

Gerald Teschl·Yifei Wang·Bing Xie·Zhe Zhou

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Abstract

In this paper, we introduce a rotation number for almost periodic Sturm-Liouville operators in the spirit of Johnson and Moser. We then prove the gap labelling theorem in terms of rotation numbers for the operator in question. To do this, we rigorously prove the almost periodicity of Green's functions.

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BibTeX RIS

Gerald Teschl, Yifei Wang, Bing Xie, Zhe Zhou. 2026-01-26. Gap Labelling for Almost Periodic Sturm-Liouville Operators. https://arxiv.org/abs/2601.18312

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