English

Lifting coarse homotopies

Geometric Topology 2025-03-03 v8 Metric Geometry

Abstract

Coarse geometry, and in particular coarse homotopy theory, has proven to be a powerful tool for approaching problems in geometric group theory and higher index theory. In this paper, we continue to develop theory in this area by proving a Coarse Lifting Lemma with respect to a certain class of bornologous surjective maps. This class is wide enough to include quotients by coarsely discontinuous group actions, which allows us to obtain results concerning the coarse fundamental group of quotients which are analogous to classical topological results for the fundamental group. As an application, we compute the fundamental group of metric cones over negatively curved compact Riemannian manifolds.

Keywords

Cite

@article{arxiv.1903.06084,
  title  = {Lifting coarse homotopies},
  author = {Thomas Weighill},
  journal= {arXiv preprint arXiv:1903.06084},
  year   = {2025}
}

Comments

Extra results on coarse semistability added

R2 v1 2026-06-23T08:08:18.738Z