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Exactness and uniform embeddability of discrete groups

Erik Guentner·Jerome Kaminker
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Abstract

We define a numerical quasi-isometry invariant of a finitely generated group, whose values parametrize the difference between the group being uniformly embeddable in a Hilbert space and the reduced C*-algebra of the group being exact.

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Erik Guentner, Jerome Kaminker. 2003-09-09. Exactness and uniform embeddability of discrete groups. https://arxiv.org/abs/math/0309166

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