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arXiv · 0910.3958

On cocycle superrigidity for Gaussian actions

Jesse Peterson·Thomas Sinclair
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Abstract

We present a general setting to investigate U_fin-cocycle superrigidity for Gaussian actions in terms of closable derivations on von Neumann algebras. In this setting we give new proofs to some U_fin-cocycle superrigidity results of S. Popa and we produce new examples of this phenomenon. We also use a result of K. Schmidt to give a necessary cohomological condition on a group representation in order for the resulting Gaussian action to be U_fin-cocycle superrigid.

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Jesse Peterson, Thomas Sinclair. 2010-03-22. On cocycle superrigidity for Gaussian actions. https://arxiv.org/abs/0910.3958

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