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arXiv · 1301.4369

Rank gradient of small covers

Darlan Girão
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Abstract

We prove that if $M \longrightarrow P$ is a small cover of a compact right-angled hyperbolic polyhedron $P$ then $M$ admits a cofinal tower of finite sheeted covers with positive rank gradient. As a corollary, if $π_1(M)$ is commensurable with the reflection group of $P$, then $M$ admits a cofinal tower of finite sheeted covers with positive rank gradient.

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Darlan Girão. 2013-01-18. Rank gradient of small covers. https://doi.org/10.2140/pjm.2013.266.23

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