Equilibrium states for dynamical systems arising from geometry

July 15 to July 19, 2019

at the

American Institute of Mathematics, San Jose, California

organized by

Keith Burns, Vaughn Climenhaga, Todd Fisher, and Dan Thompson

Original Announcement

This workshop will address questions of existence and uniqueness of equilibrium states, and their statistical properties, for dynamical systems arising from geometry, particularly geodesic flows.

Geodesic flows are an important class of systems, whose study mirrors the historical development of the theory of dynamical systems; many major theoretical results were obtained first for geodesic flows, before being generalized to broader classes of systems. The study of geodesic flow for a closed manifold of negative curvature is by now classical. Directions of contemporary study include weakening the hypotheses on the curvature (for example, to non-positive curvature or the assumption of no focal points), weakening the compactness assumption to allow for cusps, and weakening the assumption that the underlying space is a Riemannian manifold (we could consider e.g. a locally CAT(-1) or CAT(0) metric space). Other cases of particular interest are the geodesic flow for the Teichmuller space of quadratic differentials, and certain classes of billiard flow.

The workshop will focus on developing the dynamical theory, particularly thermodynamic formalism, in the various settings described above, building on recent breakthroughs in this area in the last few years.

The main topics for the workshop are:

Material from the workshop

A list of participants.

The workshop schedule.

A report on the workshop activities.

A list of open problems.

Workshop Videos

Papers arising from the workshop:

Lyapunov exponents and nonadapted measures for dispersing billiards
by  Vaughn Climenhaga, Mark Demers, Yuri Lima, Hongkun Zhang
Multifractal analysis of geodesic flows on surfaces without focal points
by  Kiho Park, Tianyu Wang
Unique equilibrium states for geodesic flows on flat surfaces with singularities
by  Benjamin Call, David Constantine, Alena Erchenko, Noelle Sawyer, Grace Work
Topological flows for hyperbolic groups
by  Ryokichi Tanaka