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arXiv · 0711.1643

A Measurable-Group-Theoretic Solution to von Neumann's Problem

Damien Gaboriau·Russell Lyons
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Abstract

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.

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BibTeXRIS

Damien Gaboriau, Russell Lyons. 2009-03-11. A Measurable-Group-Theoretic Solution to von Neumann's Problem. https://arxiv.org/abs/0711.1643

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