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arXiv · 2002.09342

Groupes pleins-topologiques [d'apr\`es Matui, Juschenko, Monod...]

Yves de Cornulier
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Abstract

This is the written version of the Bourbaki seminar given in January 2013 and published in 2014 (modulo an additional early reference added subsequently). It describes the first construction of infinite, finitely generated amenable simple groups. It starts with a general study of topological-full groups, along with indications on the first appearances of such groups. Then the theorem is proved, namely that the derived subgroup of the topological-full group of an infinite minimal subshift is both simple and finitely generated (Matui 2006) and amenable (Juschenko-Monod 2013, after being conjectured by Grigorchuk-Medynets). Some other properties of these groups are discussed. None of the numerous subsequent developments since 2013 are mentioned.

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Yves de Cornulier. 2020-02-21. Groupes pleins-topologiques [d'apr\`es Matui, Juschenko, Monod...]. https://arxiv.org/abs/2002.09342

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