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arXiv · 0806.1188

Four-free groups and hyperbolic geometry

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.

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Marc Culler, Peter B. Shalen. 2008-06-06. Four-free groups and hyperbolic geometry. https://doi.org/10.1112/jtopol/jtr028

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