Speaker: Iosif Polterovich (University of Montreal) Title: The spectral function and the remainder in local Weyl's law: View from below Abstract. Consider the Laplace operator on a compact manifold. How small is the error term in Weyl's law for the distribution of eigenvalues? It is a fascinating question with remarkable links to number theory: in particular, on a flat square torus this question is equivalent to the famous Gauss circle problem. In order to understand which upper bounds on the remainder one may hope for, it is useful to study the estimates from below. The talk focuses on the lower bounds for the spectral function of the Laplacian and for the pointwise error term in Weyl's law. I will first discuss some general results and then explain how the techniques of thermodynamic formalism for hyperbolic flows yield stronger estimates on negatively curved manifolds. This is a joint work with Dmitry Jakobson (McGill).