##### Department of Mathematics,

University of California San Diego

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### Math 211B - Group Actions Seminar

## Petr Naryshkin

#### WWU Münster

## Borel asymptotic dimension of the boundary action of a hyperbolic group

##### Abstract:

We give a new short proof of the theorem due to Marquis and Sabok, which states that the orbit equivalence relation induced by the action of a finitely generated hyperbolic group on its Gromov boundary is hyperfinite. Our methods permit moreover to show that every such action has finite Borel asymptotic dimension. This is a joint work with Andrea Vaccaro.

Host: Brandon Seward

### October 12, 2023

### 10:00 AM

APM 7321 and Zoom ID 967 4109 3409

Research Areas

Ergodic Theory and Dynamical Systems****************************