Free amalgamation and automorphism groups
Logic
2014-06-05 v1
Abstract
Let L be a countable elementary language, N be a Fraisse limit. We consider free amalgamation for L-structures where L is arbitrary. If free amalgamation for finitely generated substructures exits in N, then it is a stationary independece relation in the sense of K.Tent and M.Ziegler [TZ12b]. Therefore Aut(N) is universal for Aut(M) for all substructures M of N. This follows by a result of I.M\"uller [Mue13] We show that c-nilpotent graded Lie algebras over a finite field and c-nilpotent groups of exponent p (c < p) with extra predicates for a central Lazard series provide examples. We replace the proof in [Bau04] of the amalgamation of c-nilpotent graded Lie algebras over a field by a correct one.
Cite
@article{arxiv.1406.1130,
title = {Free amalgamation and automorphism groups},
author = {Andreas Baudisch},
journal= {arXiv preprint arXiv:1406.1130},
year = {2014}
}