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arXiv · 1407.0475

On universal modular symbols

Bruno Kahn·Fei Sun
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Abstract

We clarify the relationship between works of Lee-Szczarba and Ash-Rudolph on the homology of the Steinberg module of a linear Tits building. This yields a simple proof of the Solomon-Tits theorem in this special case. We also give a (weak) relationship between this combinatorics and the one studied by van der Kallen, Suslin and Nesterenko to compute the homology of the general linear group with constant coefficients.

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Bruno Kahn, Fei Sun. 2014-07-02. On universal modular symbols. https://arxiv.org/abs/1407.0475

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