# A Groupoid Picture of Elek Algebras

**Authors:** Clemens Borys

arXiv: 1908.01329 · 2019-08-06

## TL;DR

This paper reinterprets Elek's construction of C*-algebras from uniformly recurrent subgroups using groupoid theory, simplifying proofs and characterizing nuclearity while linking to group dynamics.

## Contribution

It provides a groupoid framework for Elek algebras, clarifying their structure and properties, and relates them to the dynamics of group actions.

## Key findings

- Simplified proofs of Elek's results
- Full characterization of nuclearity of the algebras
- Connection established between groupoid models and group dynamics

## Abstract

We describe a construction by G\'abor Elek, associating C*-algebras with uniformly recurrent subgroups, in the language of groupoid C*-algebras. This allows us to simplify several proofs in the original paper and fully characterise their nuclearity. We furthermore relate our groupoids to the dynamics of the group acting on its uniformly recurrent subgroup.

## Figures

1 figure with captions in the complete paper: https://tomesphere.com/paper/1908.01329/full.md

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Source: https://tomesphere.com/paper/1908.01329