English

Weyl asymptotics for singular metrics with a variable boundary degeneracy exponent

Spectral Theory 2026-05-25 v2

Abstract

We consider a compact smooth manifold XX of dimension n+1n+1 with boundary M=XM=\partial X. In a collar neighborhood of MM, we assume that the metric has the form g=uαgˉg=u^{-\alpha}\bar g, where uu is a boundary defining function, αC1(M;[0,2))\alpha\in C^1(M;[0,2)) and gˉ\bar g is a C1C^1 Riemannian metric up to MM. Since α<2\alpha<2, the boundary lies at finite gg-distance and (X,g)(X,g) is a singular metric space. We study the Weyl asymptotics of the Friedrichs Laplacian _g\triangle\_g when the degeneracy exponent α\alpha varies along MM. If the maximum α_max\alpha\_{\mathrm{max}} of α\alpha on MM is strictly larger than the critical value α_c=2n+1\alpha\_c=\frac{2}{n+1}, then we prove that the points where α\alpha is close to α_max\alpha\_{\mathrm{max}} govern the leading term in the Weyl asymptotics. If α_maxα_c\alpha\_{\mathrm{max}}\leq\alpha\_c, then the leading term is governed by the truncated volume \vol_g({\dist(,M)>λ1/2})\vol\_g(\{\dist(\cdot,M)>\lambda^{-1/2}\}). When the maximum set of α\alpha is Morse-Bott, we compute the associated constants and the logarithmic corrections. To the best of our knowledge, this is the first Weyl law in this setting with a boundary-dependent degeneracy exponent. The results highlight a sharp transition at α_c\alpha\_c between a boundary-dominated non-classical regime and a truncated-volume regime.

Keywords

Cite

@article{arxiv.2603.15256,
  title  = {Weyl asymptotics for singular metrics with a variable boundary degeneracy exponent},
  author = {Yves Colin de Verdière and Charlotte Dietze and Emmanuel Trélat},
  journal= {arXiv preprint arXiv:2603.15256},
  year   = {2026}
}
R2 v1 2026-07-01T11:22:15.533Z