Generic properties of the Laplace spectrum and eigenfunctions

Abstract

We prove that the spectrum of the Laplace--Beltrami operator on compact Riemannian manifolds without boundary is generically linearly independent over $\mathbb{Q}$. Furthermore, we prove that pointwise products of eigenfunctions generically are linearly independent. The proof is based on conformal perturbations of the metric. The result implies in particular that generically the truncation of the continuous functions on $M$ by spectral projections of the Laplace operator is given by symmetric matrices.

arXiv comment22 pages