Automorphism groups of Boolean powers with ample generics
Rings and Algebras
2025-09-25 v1 Group Theory
Logic
Abstract
Let be a finite non-abelian simple Mal'cev algebra, such as for example a finite simple non-abelian group or a finite simple non-zero ring. We show that the automorphism group of a filtered Boolean power of by the countable atomless Boolean algebra has ample generics. This uses the decomposition of that automorphism group as a semidirect product of a certain closure of a Boolean power of the automorphism group of by and the stabiliser of finitely many points in the homeomorphism group Homeo of the Cantor space by the authors. As an intermediate step, we show that pointwise stabilisers in Homeo have ample generics, which extends the result of Kwiatkowska that Homeo has ample generics.
Cite
@article{arxiv.2509.20121,
title = {Automorphism groups of Boolean powers with ample generics},
author = {Peter Mayr and Nik Ruškuc},
journal= {arXiv preprint arXiv:2509.20121},
year = {2025}
}