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arXiv · 1111.7016

On the genus of infinite groups

Iain Aitchison·Lawrence Reeves
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Abstract

We associate to each finite presentation of a group G a compact CW-complex that is a 3-manifold in the complement of a point, and whose fundamental group is isomorphic to G. We use this complex to define a notion of genus for G and give examples, and also define a notion of `closed group'. A group has genus 0 if and only if it is the fundamental group of a compact orientable 3-manifold.

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Iain Aitchison, Lawrence Reeves. 2011-11-29. On the genus of infinite groups. https://arxiv.org/abs/1111.7016

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