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arXiv · 2506.15494

Profinite rigidity of crystallographic groups arising from Lie theory

Abstract

We prove that every finite direct product of crystallographic groups arising from an irreducible root system (in the sense of Lie theory) is profinitely rigid (equiv. first-order rigid). This is a generalization of recent proofs of profinite rigidity of affine Coxeter groups [1, 7, 22]. Our proof uses model theory.

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BibTeXRIS

Davide Carolillo, Gianluca Paolini. 2025-06-18. Profinite rigidity of crystallographic groups arising from Lie theory. https://arxiv.org/abs/2506.15494

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