English

Profinite rigidity properties of central extensions of 2-orbifold groups

Group Theory 2026-02-25 v2

Abstract

We extend Wilkes' results on the profinite rigidity of SFSs to the setting of central extensions of 2-orbifold groups with higher-rank centre. We prove that both rigid and non-rigid phenomena arise in this setting and that the non-rigid phenomena are transient in the sense that if G^1G^2\widehat{G}_1 \cong \widehat{G}_2, then G1×ZG2×ZG_1 \times \mathbb{Z} \cong G_2 \times \mathbb{Z}.

Keywords

Cite

@article{arxiv.2304.01105,
  title  = {Profinite rigidity properties of central extensions of 2-orbifold groups},
  author = {Paweł Piwek},
  journal= {arXiv preprint arXiv:2304.01105},
  year   = {2026}
}

Comments

45 pages. Removed the unnecessary assumption of at least 2 cone points. Comments welcome!