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arXiv · 1805.12382

Random outer automorphisms of free groups: Attracting trees and their singularity structures

Ilya Kapovich·Joseph Maher·Catherine Pfaff·Samuel J. Taylor
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Abstract

We prove that a "random" free group outer automorphism is an ageometric fully irreducible outer automorphism whose ideal Whitehead graph is a union of triangles. In particular, we show that its attracting (and repelling) tree is a nongeometric $\mathbb R$-tree all of whose branch points are trivalent

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Ilya Kapovich, Joseph Maher, Catherine Pfaff, Samuel J. Taylor. 2018-05-31. Random outer automorphisms of free groups: Attracting trees and their singularity structures. https://arxiv.org/abs/1805.12382

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