Dismantlable classifying space for the family of parabolic subgroups of a relatively hyperbolic group
arXiv:1602.04863 · doi:10.1017/S147474801700010X
Abstract
Let be a group hyperbolic relative to a finite collection of subgroups . Let be the family of subgroups consisting of all the conjugates of subgroups in , all their subgroups, and all finite subgroups. Then there is a cocompact model for . This result was known in the torsion-free case. In the presence of torsion, a new approach was necessary. Our method is to exploit the notion of dismantlability. A number of sample applications are discussed.
Version accepted for publication in J. Inst. Math. Jussieu