Virtually nilpotent groups with finitely many orbits under automorphisms

Autor: Bastos, Raimundo, Dantas, Alex C., de Melo, Emerson
Rok vydání: 2020
Předmět:
Zdroj: Archiv der Mathematik (2021). The final publication is available at https://link.springer.com/article/10.1007/s00013-020-01566-w
Druh dokumentu: Working Paper
DOI: 10.1007/s00013-020-01566-w
Popis: Let $G$ be a group. The orbits of the natural action of $\Aut(G)$ on $G$ are called "automorphism orbits" of $G$, and the number of automorphism orbits of $G$ is denoted by $\omega(G)$. Let $G$ be a virtually nilpotent group such that $\omega(G)< \infty$. We prove that $G = K \rtimes H$ where $H$ is a torsion subgroup and $K$ is a torsion-free nilpotent radicable characteristic subgroup of $G$. Moreover, we prove that $G^{'}= D \times \Tor(G^{'})$ where $D$ is a torsion-free nilpotent radicable characteristic subgroup. In particular, if the maximum normal torsion subgroup $\tau(G)$ of $G$ is trivial, then $G^{'}$ is nilpotent.
Databáze: arXiv