Presentations for subgroups of Artin groups
Abstract
For a connected graph L, let G(L) be a group with generators the vertex set of L, subject only to the relations that the ends of each edge commute. Now let H(L) be the kernel of the homomorphism from G(L) to the integers that takes each vertex to 1. M. Bestvina and N. Brady have shown that finiteness properties of H(L) are intimately related to the topology of the clique complex of L. We give a presentation for H(L), with generators the edges of L, and an infinite family of relators for each 1-cycle in L. In the case when the clique complex for L is simply-connected, we give a finite presentation for H(L), with generators the edges (or 2-cliques) of L, and two relators for each 3-clique in L.
Cite
@article{arxiv.1210.6585,
title = {Presentations for subgroups of Artin groups},
author = {Warren Dicks and Ian J. Leary},
journal= {arXiv preprint arXiv:1210.6585},
year = {2012}
}
Comments
Preprint version, not published version. Previously available on Dave Benson's archive