The Bianchi groups are subgroup separable on geometrically finite subgroups

Ian Agol; Darren D. Long; Alan W. Reid

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arXiv · math/9811114

The Bianchi groups are subgroup separable on geometrically finite subgroups

Ian Agol·Darren D. Long·Alan W. Reid

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Abstract

We show that for certain arithmetic groups, geometrically finite subgroups are the intersection of finite index subgroups containing them. Examples are the Bianchi groups and the Seifert-Weber dodecahedral space. In particular, for manifolds commensurable with these groups, immersed incompressible surfaces lift to embeddings in a finite sheeted covering.

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Ian Agol, Darren D. Long, Alan W. Reid. 2001-01-05. The Bianchi groups are subgroup separable on geometrically finite subgroups. https://arxiv.org/abs/math/9811114

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