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arXiv · 2311.14445

Spectral instability of coverings

Sugata Mondal·Werner Ballmann
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Abstract

We study the behaviour of eigenvalues, below the bottom of the essential spectrum, of the Laplacian under finite Riemannian coverings of complete and connected Riemannian manifolds. We define spectral stability and instability of such coverings. Among others, we provide necessary conditions for stability or, equivalently, sufficient conditions for instability.

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Sugata Mondal, Werner Ballmann. 2023-11-24. Spectral instability of coverings. https://arxiv.org/abs/2311.14445

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