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arXiv · 2512.19248

Small eigenvalues of pseudo-Laplacians

Werner Ballmann·Sugata Mondal·Panagiotis Polymerakis
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Abstract

We extend the Otal-Rosas bound on the number of small eigenvalues of the Laplacian on a hyperbolic surface to the small eigenvalues of pseudo-Laplacians. In the process, we extend the work of Colin de Verdi\`ere on the spectral theory of pseudo-Laplacians to hyperbolic surfaces with more than one cusp.

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Werner Ballmann, Sugata Mondal, Panagiotis Polymerakis. 2025-12-22. Small eigenvalues of pseudo-Laplacians. https://arxiv.org/abs/2512.19248

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