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arXiv · 0912.1091

Relative Property (T) and the Vanishing of the first $\ell^2$-Betti number

Talia Fernós
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Abstract

In this paper, we show that certain families with relative property (T) have trivial first $\ell^2$-Betti number. We apply this to the elementary matrix group $\EL_n(\R)$ where $\R$ is any countable unital ring of characteristic 0.

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Talia Fernós. 2009-12-06. Relative Property (T) and the Vanishing of the first $\ell^2$-Betti number. https://arxiv.org/abs/0912.1091

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