Time: 4:40 p.m.
Location: 106 McAllister Building
Name: Danny Calegari
Affiliation: Caltech
Title: Quasigeodesic flows on 3-manifolds
Abstract: A quasigeodesic flow on a (closed) hyperbolic 3-manifold gives rise to a dynamical package, analogous to that obtained from a pseudo-Anosov automorphism of a (higher genus) surface. One obtains a universal circle and a pair of invariant laminations, analogous to the stable/unstable foliations of a pseudo-Anosov flow, but derived entirely from coarse and macroscopic properties of the flow on the universal cover. There are two immediate corollaries of this structure theory:
1. Nonexistence results: infinitely many closed hyperbolic 3-manifolds admit no quasigeodesic flow
2. Thurston norm: the unit ball in the (dual) Thurston norm is the convex hull of the Euler classes of quasigeodesic flows on the manifold.
