English

Uniform bounds for Neumann heat kernels and their traces in convex sets

Analysis of PDEs 2026-01-13 v1 Spectral Theory

Abstract

We prove a bound on the heat trace of the Neumann Laplacian on a convex domain that captures the first two terms in its small-time expansion, but is valid for all times and depends on the underlying domain only through very simple geometric characteristics. This is proved via a precise and uniform expansion of the on-diagonal heat kernel close to the boundary. Most of our results are valid without the convexity assumption and we also consider two-term asymptotics for the heat trace for Lipschitz domains.

Keywords

Cite

@article{arxiv.2601.07341,
  title  = {Uniform bounds for Neumann heat kernels and their traces in convex sets},
  author = {Rupert L. Frank and Simon Larson},
  journal= {arXiv preprint arXiv:2601.07341},
  year   = {2026}
}

Comments

The paper extends part of what was contained in an earlier version of arXiv:2407.11808