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arXiv · 2103.06679

Trou spectral dans les groupes simples

Weikun He·Nicolas de Saxcé
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Abstract

Nous montrons la propri\'et\'e du trou spectral pour la famille des graphes de Cayley obtenus par r\'eduction modulo $q$ d'un sous-groupe de $\mathrm{SL}_d(\mathbb{Z})$ dont l'adh\'erence de Zariski est un $\mathbb{Q}$-groupe simple. -- We show a spectral gap property for the family of Cayley graphs obtained by reduction modulo $q$ of a subgroup of $\mathrm{SL}_d(\mathbb{Z})$ whose Zariski closure is a simple $\mathbb{Q}$-group.

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Weikun He, Nicolas de Saxcé. 2021-03-11. Trou spectral dans les groupes simples. https://arxiv.org/abs/2103.06679

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