English

Computing the Cech cohomology of decomposition spaces

Geometric Topology 2017-12-05 v1 Group Theory

Abstract

A line pattern in a free group FF is defined by a malnormal collection of cyclic subgroups. Otal defined a decomposition space D\mathcal{D} associated to a line pattern. We provide an algorithm that computes a presentation for the \v{C}ech cohomology of D\mathcal{D}, thought of as a FF-module. This answers a relative version of a question of Epstein about boundaries of hyperbolic groups.

Keywords

Cite

@article{arxiv.1712.00780,
  title  = {Computing the Cech cohomology of decomposition spaces},
  author = {Benjamin Barrett},
  journal= {arXiv preprint arXiv:1712.00780},
  year   = {2017}
}

Comments

10 pages, 2 figures