# Some virtually special hyperbolic 3-manifold groups

### Eric Chesebro

University of Montana, Missoula, USA### Jason DeBlois

University of Pittsburgh, USA### Henry Wilton

University of Cambridge, Great Britain

## Abstract

Let $M$ be a complete hyperbolic 3-manifold of finite volume that admits a decomposition into right-angled ideal polyhedra. We show that $M$ has a deformation retraction that is a virtually special square complex, in the sense of Haglund and Wise and deduce that such manifolds are virtually fibered. We generalise a theorem of Haglund and Wise to the relatively hyperbolic setting and deduce that ${\pi_1}M$ is LERF and that the geometrically finite subgroups of ${\pi_1}M$ are virtual retracts. Examples of 3-manifolds admitting such a decomposition include augmented link complements. We classify the low-complexity augmented links and describe an infinite family with complements not commensurable to any 3-dimensional reflection orbifold.

## Cite this article

Eric Chesebro, Jason DeBlois, Henry Wilton, Some virtually special hyperbolic 3-manifold groups. Comment. Math. Helv. 87 (2012), no. 3, pp. 727–787

DOI 10.4171/CMH/267