Quasi-conical domains with embedded eigenvalues

David Krejcirik; Vladimir Lotoreichik

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arXiv · 2205.08172

Quasi-conical domains with embedded eigenvalues

David Krejcirik·Vladimir Lotoreichik

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Abstract

The spectrum of the Dirichlet Laplacian on any quasi-conical open set coincides with the non-negative semi-axis. We show that there is a connected quasi-conical open set such that the respective Dirichlet Laplacian has a positive (embedded) eigenvalue. This open set is constructed as the tower of cubes of growing size connected by windows of vanishing size. Moreover, we show that the sizes of the windows in this construction can be chosen so that the absolutely continuous spectrum of the Dirichlet Laplacian is empty.

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BibTeX RIS

David Krejcirik, Vladimir Lotoreichik. 2022-05-17. Quasi-conical domains with embedded eigenvalues. https://arxiv.org/abs/2205.08172

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