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