Exponential mixing via additive combinatorics

Seminar: 
Group Actions, Geometry and Dynamics
Event time: 
Monday, April 3, 2023 - 4:00pm
Location: 
LOM 206
Speaker: 
Osama Khalil
Speaker affiliation: 
UIC
Event description: 

The Bowen-Ruelle conjecture predicts that geodesic flows on negatively curved manifolds are exponentially mixing with respect to all their equilibrium states. In a breakthrough in ‘98, Dolgopyat pioneered a method rooted in the thermodynamic formalism that settled the conjecture for flows satisfying certain strong regularity hypotheses. Soon after, Liverani introduced a more intrinsic refinement of Dolgopyat’s method which overcame these regularity limitations while simultaneously producing more precise rates of mixing, albeit at the price of being limited to smooth invariant measures. Despite these important developments, the conjecture remains open in general even for the measure of maximal entropy. In this talk, I will describe a new approach leveraging inverse theorems in additive combinatorics to overcome the limitations in Liverani’s approach in a concrete algebraic setting, namely the setting of geometrically finite quotients of rank one symmetric spaces.