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arXiv · 1011.5392

Homotopy invariance for homology of linear groups: the case SL_4

Matthias Wendt
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Abstract

In this paper, we investigate homotopy invariance for homology of SL_4. For any commutative ring, the group E_4(R[t]) acts on a simplicial complex whose contractibility implies homotopy invariance. We show that for a local factorial ring R, this complex satisfies the CAT(0)-property for the induced length metric from the Bruhat-Tits building.

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Matthias Wendt. 2011-08-10. Homotopy invariance for homology of linear groups: the case SL_4. https://arxiv.org/abs/1011.5392

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