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Register a new userFour-free groups and hyperbolic geometry
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Authors
Marc Culler
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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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We prove that there are only finitely many conjugacy classes of arithmetic maximal hyperbolic reflection groups.
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