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arXiv · 2506.18875

Spectrum of the Laplacian in waveguide shaped surfaces

Diana C. S. Bello
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Abstract

Let $-\Delta_{\cal S}$ be the Laplace operator in ${\cal S} \subset \mathbb{R}^3$ on a waveguide shaped surfaces, i.e., ${\cal S}$ is built by translating a closed curve in a constant direction along an unbounded spatial curve. Under the condition that the tangent vector of the reference curve admits a finite limit at infinity, we find the essential spectrum of $-\Delta_{\cal S}$ and discuss conditions under which discrete eigenvalues emerge. Furthermore, we analyze the Laplacian in the case of a broken sheared waveguide shaped surface.

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Diana C. S. Bello. 2025-06-23. Spectrum of the Laplacian in waveguide shaped surfaces. https://arxiv.org/abs/2506.18875

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