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arXiv · 1302.2293

An l^{p}-Version of von Neumann Dimension for Representations of Equivalence Relations

Ben Hayes
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Abstract

In our previous paper, "l^{p}-Version of von Neumann Dimension for Banach Space Representations of Sofic Groups," we define an extended version of von Neumann dimension for actions of a sofic group on a Banach space. This dimension was studied especially for the translation action of G on l^{p}(G), as well as the multiplication on the non-commutative L^{p} space associated with the group von Neumann algebra. We discuss how one can similarly define an extended dimension for representations of an equivalence relation. We also define an analogue of l^{2}-Betti numbers for equivalence relations in the l^{p}-case, this may shed some light on the conjectured relation between cost and first l^{2}-Betti number.

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Ben Hayes. 2013-02-10. An l^{p}-Version of von Neumann Dimension for Representations of Equivalence Relations. https://arxiv.org/abs/1302.2293

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