The eigenvalues of the Laplacian on domains with small slits

Luc Hillairet; Chris Judge

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arXiv · 0802.2597

The eigenvalues of the Laplacian on domains with small slits

Luc Hillairet·Chris Judge

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Abstract

We introduce a small slit into a planar domain and study the resulting effect upon the eigenvalues of the Laplacian. In particular, we show that as the length of the slit tends to zero, each real-analytic eigenvalue branch tends to an eigenvalue of the original domain. By combining this with our earlier work (arXiv:math/0703616), we obtain the following application: The generic multiply connected polygon has simple spectrum.

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Luc Hillairet, Chris Judge. 2008-02-19. The eigenvalues of the Laplacian on domains with small slits. https://arxiv.org/abs/0802.2597

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