Critical exponent gap

Seminar: 
Group Actions, Geometry and Dynamics
Event time: 
Monday, October 21, 2024 - 4:15pm
Location: 
KT205
Speaker: 
Omri Solan
Speaker affiliation: 
Hebrew University
Event description: 

We will discuss the following result. For every geometrically finite Kleinian group Γ < SL2() there is εΓ such that for every g  SL2() the intersection  gΓg-1 ∩ SL2() is either a lattice or a has critical exponent δ(gΓg-1 ∩ SL2()) ≤ 1-εΓ

This result extends Margulis-Mohammadi and Bader-Fisher-Milier-Strover. 

We will discuss some ideas of the proof. We will focus on the applications of a new ergodic component, of preservation of entropy in a direction.