On the congruence subgroup problem for branch groups

Alejandra Garrido

doi:10.1007/s11856-016-1402-x

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arXiv · 1405.3237

On the congruence subgroup problem for branch groups

Alejandra Garrido

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Abstract

We answer a question of Bartholdi, Siegenthaler and Zalesskii, showing that the congruence subgroup problem for branch groups is independent of the branch action on a tree. We prove that the congruence topology of a branch group is determined by the group; specifically, by its structure graph, an object first introduced by Wilson. We also give a more natural definition of this graph.

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BibTeX RIS

Alejandra Garrido. 2014-07-11. On the congruence subgroup problem for branch groups. https://doi.org/10.1007/s11856-016-1402-x

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