A Measurable-Group-Theoretic Solution to von Neumann's Problem
نویسندگان
چکیده
We give a positive answer, in the measurable-group-theory context, to von Neumann’s problem of knowing whether a non-amenable countable discrete group contains a non-cyclic free subgroup. We also get an embedding result of the free-group von Neumann factor into restricted wreath product factors. 2000 Mathematical Subject Classification: 37A20, 20E05, 82B43, 05C80
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