Congruence RFRS towers

Ian Agol; Matthew Stover

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arXiv · 1912.10283

Congruence RFRS towers

Ian Agol·Matthew Stover

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Abstract

We describe a criterion for a real or complex hyperbolic lattice to admit a RFRS tower that consists entirely of congruence subgroups. We use this to show that certain Bianchi groups $\mathrm{PSL}(\mathcal{O}_d)$ are virtually fibered on congruence subgroups, and also exhibit the first examples of RFRS Kähler groups that are not a subgroup of a product of surface groups and abelian groups.

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Ian Agol, Matthew Stover. 2019-12-21. Congruence RFRS towers. https://arxiv.org/abs/1912.10283

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