Colloquium ICJ

# One can hear the shape of a nearly circular ellipse.

## by Steven Zelditch (Northwestern university)

Europe/Paris
Salle Fokko (UCBL-Braconnier)

### Salle Fokko

#### UCBL-Braconnier

21 av Claude Bernard, 69100 VILLEURBANNE
Description

My talk is about the well-known inverse spectral problem'' for convex bounded smooth plane domains, i.e. the Kac problem `can you hear the shape of a drum'. The problem is to determine the domain from the eigenvalues of the Laplacian with Dirichlet (or Neumann) boundary conditions. It has long been conjectured that ellipses are uniquely determined by their eigenvalues. My talk is about a recent result with Hamid Hezari which proves that this is true if the ellipse has small eccentricity.

Organized by

Christophe Garban