On the geometry of Outer space

Vogtmann, Karen

doi:10.1090/S0273-0979-2014-01466-1

On the geometry of Outer space
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Bull. Amer. Math. Soc. 52 (2015), 27-46 Request permission

Abstract:

Outer space is a space of graphs used to study the group $\mathrm {Out}(F_n)$ of outer automorphisms of a finitely generated free group. We discuss an emerging metric theory for Outer space and some applications to $\mathrm {Out}(F_n)$.

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