A branch group with unsolvable conjugacy problem
Group Theory
2025-10-21 v2
Abstract
We prove that every finitely generated residually finite group can be embedded in a finitely generated branch group such that two elements in are conjugate in if and only if they are conjugate in . As an application we construct a finitely generated branch group with solvable word problem and unsolvable conjugacy problem and thereby answer a question of Bartholdi, Grigorchuk, and \v{S}uni\'{k}.
Cite
@article{arxiv.2509.12161,
title = {A branch group with unsolvable conjugacy problem},
author = {Alex Bishop and Eduard Schesler},
journal= {arXiv preprint arXiv:2509.12161},
year = {2025}
}