English

Determining the action dimension of an Artin group by using its complex of abelian subgroups

Geometric Topology 2017-06-21 v2 Group Theory

Abstract

Suppose that (W,S)(W,S) is a Coxeter system with associated Artin group AA and with a simplicial complex LL as its nerve. We define the notion of a "standard abelian subgroup" in AA. The poset of such subgroups in AA is parameterized by the poset of simplices in a certain subdivision LL_\oslash of LL. This complex of standard abelian subgroups is used to generalize an earlier result from the case of right-angled Artin groups to case of general Artin groups, by calculating, in many instances, the smallest dimension of a manifold model for BABA. (This is the "action dimension" of AA denoted actdim AA.) If Hd(L;Z/2)0H_d(L; \mathbb Z/2)\neq 0, where d=dimLd=\dim L, then actdim A2d+2A \ge 2d+2. Moreover, when the K(π,1)K(\pi,1)-Conjecture holds for AA, the inequality is an equality.

Keywords

Cite

@article{arxiv.1608.03572,
  title  = {Determining the action dimension of an Artin group by using its complex of abelian subgroups},
  author = {Michael W. Davis and Jingyin Huang},
  journal= {arXiv preprint arXiv:1608.03572},
  year   = {2017}
}

Comments

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