Semiclassical analysis, geometric representation and quantum ergodicity

Abstract

Quantum Ergodicity (QE) is a classical topic in spectral geometry, which states that on a compact Riemannian manifold whose geodesic flow is ergodic with respect to the Liouville measure, the Laplacian has a density one subsequence of eigenfunctions that tends to be equidistributed. In this talk, we present the QE for unitary flat bundles. By using a mixture of semiclassical and geometric quantizations, we can deal with the high frequency eigensections of a series of unitary flat bundles simultaneously. We will also give some applications on flat sphere bundles over hyperbolic surfaces.