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arXiv · 2304.01105

Profinite rigidity properties of central extensions of 2-orbifold groups

Paweł Piwek
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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 $\widehat{G}_1 \cong \widehat{G}_2$, then $G_1 \times \mathbb{Z} \cong G_2 \times \mathbb{Z}$.

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Paweł Piwek. 2023-04-03. Profinite rigidity properties of central extensions of 2-orbifold groups. https://doi.org/10.2140/agt.2026.26.565

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