Heegaard genus and Property 'tau' for hyperbolic 3-manifolds

D. D. Long; A. Lubotzky; A. W. Reid

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arXiv · 0709.0101

Heegaard genus and Property 'tau' for hyperbolic 3-manifolds

D. D. Long·A. Lubotzky·A. W. Reid

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Abstract

We show that any finitely generated non-elementary Kleinian group has a co-final family of finite index normal subgroups with respect to which it has Property $τ$. As a consequence, any closed hyperbolic 3-manifold has a co-final family of finite index normal subgroups for which the infimal Heegaard gradient is positive.

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BibTeX RIS

D. D. Long, A. Lubotzky, A. W. Reid. 2007-09-02. Heegaard genus and Property 'tau' for hyperbolic 3-manifolds. https://arxiv.org/abs/0709.0101

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