Four-free groups and hyperbolic geometry
Geometric Topology
2020-11-04 v4
Abstract
We give new information about the geometry of closed, orientable hyperbolic 3-manifolds with 4-free fundamental group. As an application we show that such a manifold has volume greater than 3.44. This is in turn used to show that if M is a closed orientable hyperbolic 3-manifold such that vol M < 3.44, then H_1(M;Z/2Z) has dimension at most 7.
Cite
@article{arxiv.0806.1188,
title = {Four-free groups and hyperbolic geometry},
author = {Marc Culler and Peter B. Shalen},
journal= {arXiv preprint arXiv:0806.1188},
year = {2020}
}
Comments
64 pages, 4 figures. This version corrects an error in the third paragraph of the proof of Lemma 13.3