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arXiv · 1308.4250

A finitely presented group of piecewise projective homeomorphisms

Yash Lodha·Justin Tatch Moore
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Abstract

In this article we will describe a finitely presented subgroup of Monod's group of piecewise projective homeomorphisms of R. This in particular provides a new example of a finitely presented group which is nonamenable and yet does not contain a nonabelian free subgroup. It is in fact the first such example which is torsion free. We will also develop a means for representing the elements of the group by labeled tree diagrams in a manner which closely parallels Richard Thompson's group F.

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Yash Lodha, Justin Tatch Moore. 2014-08-01. A finitely presented group of piecewise projective homeomorphisms. https://arxiv.org/abs/1308.4250

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