- 05-244 Lled\'o, Fernando and Post, Olaf
- Generating spectral gaps by geometry
Jul 15, 05
(auto. generated ps),
of related papers
Abstract. Motivated by the analysis of Schr\"odinger operators with periodic potentials we consider the following abstract situation: Let $\Delta_X$ be the Laplacian on a non-compact Riemannian covering manifold $X$ with a discrete isometric group $\Gamma$ acting on it such that the quotient $X/\Gamma$ is a compact manifold. We prove the existence of a finite number of spectral gaps for the operator $\Delta_X$ associated with a suitable class of manifolds $X$ with non-abelian covering transformation groups $\Gamma$. This result is based on the non-abelian Floquet theory as well as the Min-Max-principle. Groups of type I specify a class of examples satisfying the assumptions of the main theorem.