English

Eigenvalue lower bounds through a generalized inradius

Spectral Theory 2025-09-24 v1 Analysis of PDEs Functional Analysis

Abstract

Lieb has shown a lower bound on the smallest Dirichlet eigenvalue of the Laplace operator in terms of a generalized inradius. We derive similar bounds for Robin eigenvalues, for eigenvalues of the polyharmonic operator and the sub-Laplacian on the Heisenberg group. We propose a method based on Hardy inequalities that is different from Lieb's approach.

Keywords

Cite

@article{arxiv.2509.18878,
  title  = {Eigenvalue lower bounds through a generalized inradius},
  author = {Rupert L. Frank and Ari Laptev and Durvudkhan Suragan},
  journal= {arXiv preprint arXiv:2509.18878},
  year   = {2025}
}

Comments

16 pages

R2 v1 2026-07-01T05:51:51.642Z