Dynamics of Aut(Fn) Actions on Group Presentations and Representations

Alexander Lubotzky

Published 2011-09-01, updated 2011-12-15Version 2

Several different areas of group theory, topology and geometry have led to the study of the action of Aut(Fn) | the automorphism group of the free group on n generators | on Hom(Fn;G) when G is either finite,compact or simple Lie group. In this survey, we describe these topics and results, with special emphasis on some similarities and with an effort to give a somewhat uniform treatment. This perspective sometimes suggests new questions, conjectures and methods borrowed from one area to another.