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On Mostow rigidity for variable negative curvature

Igor Belegradek
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Abstract

We prove a finiteness theorem for the class of complete finite volume Riemannian manifolds with pinched negative sectional curvature, fixed fundamental group, and of dimension $>2$. One of the key ingredients is that the fundamental group of such a manifold does not admit a small nontrivial action on an $R$-tree.

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Igor Belegradek. 2000-03-15. On Mostow rigidity for variable negative curvature. https://arxiv.org/abs/math/0003091

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