Year: 2010
Type: article
Abstract: We prove, under a technical assumption, that the abstract commensurator of a group that splits over a cyclic subgroup is not finitely generated. This applies in particular to free groups, surface groups, and more generally to all torsion-free word-hyperbolic groups with infinite outer automorphism group and abelianization of rank at least 2. On the other hand, we remark that the condition on the outer automorphism group cannot be removed.
Source: Journal of Group Theory
DOI: 10.1515/jgt.2010.021
Authors: L. Bartholdi, O. Bogopolski
Language: English
Subfield: Geometry and Topology
Field: Mathematics
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2951781514
