Videos

Pathways Workshop: Topological and Geometric Structures in Low Dimensions & Geometry and Dynamics for Discrete Subgroups of Higher Rank Lie Groups: Criterion for Finiteness of BMS Measure

Presenter
January 22, 2026
Keywords:
  • low-dimensional topology
  • geometric structures
  • homogeneous dynamics
  • Anosov representations
  • Higher rank Lie groups
  • symmetric spaces of non- compact type
MSC:
  • 57M50 - General geometric structures on low-dimensional manifolds
  • 57M60 - Group actions on manifolds and cell complexes in low dimensions
  • 57N16 - Geometric structures on manifolds of high or arbitrary dimension
  • 57S25 - Groups acting on specific manifolds
  • 22E40 - Discrete subgroups of Lie groups
  • 22F30 - Homogeneous spaces
  • 37E05 - Dynamical systems involving maps of the interval
  • 37E10 - Dynamical systems involving maps of the circle
  • 37E30 - Dynamical systems involving homeomorphisms and diffeomorphisms of planes and surfaces
  • 37E35 - Flows on surfaces
  • 30F60 - Teichmüller theory for Riemann surfaces
  • 32G15 - Moduli of Riemann surfaces
  • Teichmüller theory (complex-analytic aspects in several variables)]
  • 30F40 - Kleinian groups (aspects of compact Riemann surfaces and uniformization)
Abstract
In many useful settings, having a finite BMS measure on a flow space allows people to normalize the BMS measure into a probability measure and facilitates powerful ergodic theoretic tools. This often leads to asymptotic estimates for counting orbital points and establishing equidistribution results. Hence, it is important to know when a dynamical system admits a finite BMS measure. In this talk, I will introduce the criterion for the finiteness of BMS measure on the unit tangent bundle of a negatively curved manifold introduced by Pit-Schapira. If time permits, I will also present my recent work that extends this criterion to the setting of discrete subgroups of higher rank semisimple Lie groups.