Propagation of quasi-particles on singular spaces. Relation to the behavior of geodesics and to certain problems of analytic number theory

We study propagation of semi-classical localized solutions of Schroedinger or wave equations (Gaussian beams) on a certain class of singular spaces. These spaces are obtained by connecting of a number of smooth manifolds by several segments. Laplacians on such spaces are defined with the help of extension theory an depend on boundary conditions in the points of gluing. Statistics of a number of Gaussian packets is governed by the behavior of geodesics on manifolds and is connected with certain problems of analytic number theory - in particular, with the problem of distribution of abstract primes.