W∗-superrigidity of mixing Gaussian actions of rigid groups
W∗-superrigidity of mixing Gaussian actions of rigid groups
复制标题
W*-刚性群混合高斯作用的超刚性
DOI:
10.1016/j.aim.2013.05.012
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发表时间:
2012
影响因子:
1.7
通讯作者:
R. Boutonnet
中科院分区:
文献类型:
--
作者:
R. Boutonnet
We generalize W∗-superrigidity results about Bernoulli actions of rigid groups to general mixing Gaussian actions. We thus obtain the following: If Γ is any ICC group which is w-rigid (ie it contains an infinite normal subgroup with the relative property (T)) then any mixing Gaussian action Γ↷ X is W∗-superrigid. More precisely, if Λ↷ Y is another free ergodic action such that the crossed-product von Neumann algebras are isomorphic L∞(X)⋊ Γ≃ L∞(Y)⋊ Λ, then the actions are conjugate. We prove a similar statement whenever Γ is a non-amenable ICC product of two infinite groups.