Linear Representations of the Automorphism Group of a Free Group

@article{Grunewald2006LinearRO,
  title={Linear Representations of the Automorphism Group of a Free Group},
  author={Fritz Grunewald and Alexander Lubotzky},
  journal={Geometric and Functional Analysis},
  year={2006},
  volume={18},
  pages={1564-1608}
}
Abstract.Let Fn be the free group on n ≥ 2 elements and Aut(Fn) its group of automorphisms. In this paper we present a rich collection of linear representations of Aut(Fn) arising through the action of finite-index subgroups of it on relation modules of finite quotient groups of Fn. We show (under certain conditions) that the images of our representations are arithmetic groups. 
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