English

Rigidity of the free factor complex

Group Theory 2023-06-12 v1 Geometric Topology

Abstract

We establish the following non-abelian analogue of the Fundamental Theorem of Projective Geometry: the natural map from Aut(Fn){\rm{Aut}}(F_n) to the automorphism group of the free-factor complex AFn\mathcal{AF}_n is an isomorphism. We also prove the corresponding theorem for the action of Out(Fn){\rm{Out}}(F_n) on the complex of conjugacy classes of free factors.

Keywords

Cite

@article{arxiv.2306.05941,
  title  = {Rigidity of the free factor complex},
  author = {Mladen Bestvina and Martin R Bridson},
  journal= {arXiv preprint arXiv:2306.05941},
  year   = {2023}
}
R2 v1 2026-06-28T11:01:05.972Z