Nous établissons que, pour tout groupe dénombrable abélien et tout sous-groupe finiment engendré de , l’ensemble des actions de sur un espace de probabilités standard qui peuvent être étendues en une action libre de sur est générique (au sens de Baire). Ce résultat étend un théorème d’Ageev, qui correspond au cas où est un groupe cyclique infini.
We show that, whenever is a countable abelian group and is a finitely-generated subgroup of , a generic measure-preserving action of on a standard atomless probability space extends to a free measure-preserving action of on . This extends a result of Ageev, corresponding to the case when is infinite cyclic.
@article{AIF_2014__64_2_607_0, author = {Melleray, Julien}, title = {Extensions of generic measure-preserving actions}, journal = {Annales de l'Institut Fourier}, volume = {64}, year = {2014}, pages = {607-623}, doi = {10.5802/aif.2859}, zbl = {06387286}, mrnumber = {3330916}, language = {en}, url = {http://dml.mathdoc.fr/item/AIF_2014__64_2_607_0} }
Melleray, Julien. Extensions of generic measure-preserving actions. Annales de l'Institut Fourier, Tome 64 (2014) pp. 607-623. doi : 10.5802/aif.2859. http://gdmltest.u-ga.fr/item/AIF_2014__64_2_607_0/
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