# An inverse spectral problem on surfaces

### Philippe Castillon

Université de Montpellier II, France

## Abstract

The purpose of this paper is to prove how the positivity of some operators on a Riemannian surface gives informations on the conformal type of the surface (the operators considered here are of the form $Δ+λK$ where $Δ$ is the Laplacian of the surface, $K$ is its curvature and $λ$ is a real number). In particular we obtain a theorem “à la Huber”: under a spectral hypothesis we prove that the surface is conformally equivalent to a Riemann surface with a finite number of points removed. This problem has its origin in the study of stable minimal surfaces.

## Cite this article

Philippe Castillon, An inverse spectral problem on surfaces. Comment. Math. Helv. 81 (2006), no. 2, pp. 271–286

DOI 10.4171/CMH/52