English

Infinitely many embedded eigenvalues for the Neumann-Poincar\'e operator in 3D

Functional Analysis 2021-07-29 v2 Spectral Theory

Abstract

This article constructs a surface whose Neumann-Poincar\'e (NP) integral operator has infinitely many eigenvalues embedded in its essential spectrum. The surface is a sphere perturbed by smoothly attaching a conical singularity, which imparts essential spectrum. Rotational symmetry allows a decomposition of the operator into Fourier components. Eigenvalues of infinitely many Fourier components are constructed so that they lie within the essential spectrum of other Fourier components and thus within the essential spectrum of the full NP operator. The proof requires the perturbation to be sufficiently small, with controlled curvature, and the conical singularity to be sufficiently flat.

Keywords

Cite

@article{arxiv.2009.04371,
  title  = {Infinitely many embedded eigenvalues for the Neumann-Poincar\'e operator in 3D},
  author = {Wei Li and Karl-Mikael Perfekt and Stephen P. Shipman},
  journal= {arXiv preprint arXiv:2009.04371},
  year   = {2021}
}
R2 v1 2026-06-23T18:25:14.720Z