Detecting the growth of free group automorphisms by their action on the homology of subgroups of finite index
Abstract
Description
We prove that if F is a finitely generated free group and f:F -> F is an automorphism with polynomial growth of degree d, then there exists a characteristic subgroup S < F of finite index such that the induced automorphism of the abelianisation of S also grows polynomially of degree d. The proof is geometric in nature and makes use of improved relative train track representatives.
59 Pages, 10 figures, excerpt from thesis to be submitted for D.Phil at the University of Oxford
59 Pages, 10 figures, excerpt from thesis to be submitted for D.Phil at the University of Oxford