English

Domains of proper discontinuity on the boundary of Outer space

Group Theory 2011-06-03 v3 Geometric Topology

Abstract

Motivated by the work of McCarthy and Papadopoulos for subgroups of mapping class groups, we construct domains of proper discontinuity in the compactified Outer space and in the projectivized space of geodesic currents for any "sufficiently large" subgroup of Out(FN)Out(F_N) (that is, a subgroup containing a hyperbolic iwip). As a corollary we prove that for N3N\ge 3 the action of Out(FN)Out(F_N) on the subset of PCurr(FN)\mathbb PCurr(F_N) consisting of all projectivized currents with full support is properly discontinuous.

Keywords

Cite

@article{arxiv.0902.4263,
  title  = {Domains of proper discontinuity on the boundary of Outer space},
  author = {Ilya Kapovich and Martin Lustig},
  journal= {arXiv preprint arXiv:0902.4263},
  year   = {2011}
}

Comments

Updated version, 16 pages; published in: Illinois J. Math. vol. 54 (2010), no. 1, pp. 89-108; special issue of IJM dedicated to Paul Schupp