Automorphisms of free groups . I Laurent Bartholdi
نویسندگان
چکیده
We describe, up to degree n, the Lie algebra associated with the automorphism group of a free group of rank n. We compute in particular the ranks of its homogeneous components, and their structure as modules over the linear group. Along the way, we infirm (but confirm a weaker form of) a conjecture by Andreadakis, and answer a question by Bryant–Gupta–Levin– Mochizuki.
منابع مشابه
Automorphisms of free groups. I — erratum
I report an error in Theorem A of Automorphisms of free groups. I , New York J. Math. 19 (2013), 395–421, where it was claimed that two filtrations of the group of IA automorphisms of a free group coincide up to torsion. In fact, using a recent result by Day and Putman, I show that, for a free group of rank 3, the opposite conclusion holds, namely that the two series differ rationally.
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