Liz Stanhope, Lewis & Clark College

Title: Using heat invariants to study the Laplace spectral geometry of orbifolds

Abstract: A Riemann orbifold is a mildly singular generalization of a Riemannian manifold. In this talk we examine the spectrum of the Laplace operator on functions, and more generally that of the Hodge Laplacian on p-forms, in order to learn about the topological structure of an orbifold. Our main tool is the list of heat invariants associated to the p-spectrum of the corresponding Hodge Laplacian. From the heat invariants of the 0-spectrum we detect the local orientability of an orbifold in any dimension. The heat invariants of the 0-spectrum together with those of the 1-spectrum are sufficient to distinguish singular orbifolds from manifolds for dimension at most three.