## Duke Mathematical Journal

### The boundary of the complex of free factors

#### Abstract

We give a description of the boundary of a complex of free factors that is analogous to E. Klarreich’s description of the boundary of a curve complex. The argument uses the geometry of folding paths developed by Bestvina and Feighn and the structure theory of trees on the boundary of Outer space developed recently by Coulbois, Hilion, Lustig, and Reynolds.

#### Article information

Source
Duke Math. J., Volume 164, Number 11 (2015), 2213-2251.

Dates
Revised: 20 August 2014
First available in Project Euclid: 13 August 2015

https://projecteuclid.org/euclid.dmj/1439470583

Digital Object Identifier
doi:10.1215/00127094-3129702

Mathematical Reviews number (MathSciNet)
MR3385133

Zentralblatt MATH identifier
1337.20040

Subjects
Primary: 20F67: Hyperbolic groups and nonpositively curved groups
Secondary: 57M07: Topological methods in group theory

#### Citation

Bestvina, Mladen; Reynolds, Patrick. The boundary of the complex of free factors. Duke Math. J. 164 (2015), no. 11, 2213--2251. doi:10.1215/00127094-3129702. https://projecteuclid.org/euclid.dmj/1439470583

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