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arXiv · 1612.01134

Distortion for Abelian Subgroups of $\mathrm{Out}(F_n)$

Derrick Wigglesworth
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Abstract

We prove that abelian subgroups of the outer automorphism group of a free group are quasi-isometrically embedded. Our proof uses recent developments in the theory of train track maps by Feighn-Handel. As an application, we prove the rank conjecture for $\mathrm{Out}(F_n)$.

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Derrick Wigglesworth. 2016-12-04. Distortion for Abelian Subgroups of $\mathrm{Out}(F_n)$. https://arxiv.org/abs/1612.01134

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