# Exceptional holonomy and related geometric structures: Examples and moduli theory

 Marston Morse Lectures Topic: Exceptional holonomy and related geometric structures: Examples and moduli theory Speaker: Simon Donaldson Affiliation: Stonybrook University Date: Wednesday, April 4 Time/Room: 2:00pm - 3:00pm/Simonyi Hall 101 Video Link: https://video.ias.edu/MarstonMorse/2018/0404-SimonDonaldson

We will discuss the constructions of compact manifolds with exceptional holonomy (in fact, holonomy $G_{2}$),  due to Joyce and Kovalev.  These both use “gluing constructions”. The first involves de-singularising quotient spaces and the second constructs a 7-manifold from “building blocks” derived from Fano threefolds.  We will explain how the local moduli theory is determined by a period map and discuss connections between the global moduli problem and Riemannian convergence theory (for manifolds with bounded Ricci curvature).