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arXiv · 2302.13266

Profinite non-rigidity of arithmetic groups

Amir Y. Weiss Behar
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Abstract

We show that for a typical high rank arithmetic lattice $Γ$, there exist finite index subgroups $Γ_{1}$ and $Γ_{2}$ such that $Γ_{1} \not\simeq Γ_{2}$ while $\widehat{Γ_{1}} \simeq \widehat{Γ_{2}}$. But there are exceptions to that rule.

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Amir Y. Weiss Behar. 2023-02-26. Profinite non-rigidity of arithmetic groups. https://arxiv.org/abs/2302.13266

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