Finitely generated subgroups of branch groups and subdirect products of just infinite groups

Autor: Rostislav Grigorchuk, Paul-Henry Leemann, Tatiana Nagnibeda
Rok vydání: 2021
Předmět:
Zdroj: Izvestiya: Mathematics. 85:1128-1145
ISSN: 1064-5632
Popis: The aim of this paper is to describe the structure of the finitely generated subgroups of a family of branch groups, which includes the first Grigorchuk group and the Gupta-Sidki 3-group. This description is made via the notion of block subgroup. We then use this to show that all groups in the above family are subgroup separable (LERF). These results are obtained as a corollary of a more general structural statement on subdirect products of just infinite groups.
22 pages, 2 figures; V3: Final version, to appear in Izvestiya: Mathematics
Databáze: OpenAIRE