Moyennabilite interieure et extensions HNN
Group Theory
2007-05-23 v3
Abstract
We present sufficient conditions for HNN extensions to be inner amenable, respectively ICC, which give necessary and sufficient criteria among Baumslag-Solitar groups. We deduce that such a group, viewed as acting on its Bass-Serre tree, contains non trivial elements which fix unbounded subtrees.
Cite
@article{arxiv.math/0505657,
title = {Moyennabilite interieure et extensions HNN},
author = {Yves Stalder},
journal= {arXiv preprint arXiv:math/0505657},
year = {2007}
}
Comments
16 pages, in french. Slightly stronger results and typographic corrections. To appear in Ann. Inst. Fourier (Grenoble)