arXiv math/07025682007-02-20math.OAmath.GR

Weak amenability of CAT(0) cubical groups

Nigel Higson, Erik Guentner

备注：: 22 pages

英文摘要：

We prove that if G is a discrete group that admits a metrically proper action on a finite-dimensional CAT(0) cube complex X, then G is weakly amenable. We do this by constructing uniformly bounded Hilbert space representations for which the quantities z^{l(g)} are matrix coefficients. Here l is a length function on G obtained from the combinatorial distance function on the complex X.

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