C*-simplicity has no local obstruction

TL;DR

This paper constructs new non-discrete C*-simple groups, providing the first examples of non-elementary C*-simple groups, thus resolving a long-standing open problem in the field.

Contribution

It introduces a novel construction method for non-discrete C*-simple groups, expanding the known class of such groups beyond those close to discrete groups.

Findings

First examples of non-elementary C*-simple groups

Construction of non-discrete C*-simple groups

Resolution of a 2006 open problem

Abstract

In 2016, I solved a problem of de la Harpe in 2006: Is there a non-discrete C*-simple group? However the solution was not fully satisfactory as the provided C*-simple groups (and their operator algebras) are very close to discrete groups. All previously known examples are of this form. In this article I give yet another construction of non-discrete C*-simple groups. The statement in the title then follows. This in particular gives the first examples of non-elementary C*-simple groups (in Wesolek's sense).