Analytic Wavefront Sets of Spherical Distributions on De Sitter Space

Abstract

In this work we determine the wavefront set of certain eigendistributions of the Laplace-Beltrami operator on the de Sitter space. Let G = SO_{1,n}(R)_e be the connected component of identity of Lorentz group and let H = SO_{1,n-1}(R)_e, a subset G. The de Sitter space dS^n, is the one-sheeted hyperboloid in R{1,n} isomorphic to G/H. A spherical distribution, is an H-invariant, eigendistribution of the Laplace-Beltrami operator on dS^n. The space of spherical distributions with eigenvalue \lambda, denoted by D'_{\lambda}(dS^n), has dimension 2. In this article we construct a basis for the space of positive-definite spherical distributions as boundary value of sesquiholomorphic kernels on the crown domains, an open G-invariant domain in dS^n_C. It contains dS^n as a G-orbit on the boundary. We characterize the analytic wavefront set for such distributions. Moreover, if a spherical distribution \Theta in D'_{\lambda}(dS^n) has the wavefront set same as one of the basis element, then it must be a constant multiple of that basis element. Using the analytic wavefront sets we show that the basis elements of D'_{\lambda}(dS^n) can not vanish in any open region.