Exactness of Free and Amenable Groups by the Construction of Ozawa Kernels
نویسنده
چکیده
We construct specific examples of Ozawa kernels for free and amenable groups. We deduce that these groups satisfy Property O and thus are exact. This gives us an alternative proof that these groups are exact, which emphasizes the link between the geometric properties of a group and exactness of its reduced C-algebra .
منابع مشابه
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We will give a brief account of (topological) amenable actions and exactness for countable discrete groups. The class of exact groups contains most of the familiar groups and yet is manageable enough to provide interesting applications in geometric topology, von Neumann algebras and ergodic theory. Mathematics Subject Classification (2000). Primary 46L35; Secondary 20F65, 37A20, 43A07.
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