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arXiv · 1904.04902

Borel's stable range for the cohomology of arithmetic groups

Bena Tshishiku
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Abstract

In this note, we remark on the range in Borel's theorem on the stable cohomology of the arithmetic groups Sp(2n,Z) and SO(n,n;Z). This improves the range stated in Borel's original papers, an improvement that was known to Borel. Our main task is a technical computation involving the Weyl group action on roots and weights. This note originally appeared as the appendix to arXiv:1711.03139.

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Bena Tshishiku. 2019-04-09. Borel's stable range for the cohomology of arithmetic groups. https://arxiv.org/abs/1904.04902

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