Certain residual properties of generalized Baumslag-Solitar groups
arXiv:2011.00166 · doi:10.1016/j.jalgebra.2021.05.001
Abstract
Let be a generalized Baumslag-Solitar group and be a class of groups containing at least one non-unit group and closed under taking subgroups, extensions, and Cartesian products of the form , where and is an isomorphic copy of for every . We give a criterion for to be residually a -group provided consists only of periodic groups. We also prove that is residually a torsion-free -group if contains at least one non-periodic group and is closed under taking homomorphic images. These statements generalize and strengthen some known results. Using the first of them, we provide criteria for a GBS-group to be a) residually nilpotent; b) residually torsion-free nilpotent; c) residually free.
19 pages, in English