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arXiv · 1704.07768

On stably trivial spin torsors over low-dimensional schemes

Matthias Wendt
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Abstract

The paper discusses stably trivial torsors for spin and orthogonal groups over smooth affine schemes over infinite perfect fields of characteristic unequal to 2. We give a complete description of all the invariants relevant for the classification of such objects over schemes of dimension at most $3$, along with many examples. The results are based on the $\mathbb{A}^1$-representability theorem for torsors and transfer of known computations of $\mathbb{A}^1$-homotopy sheaves along the sporadic isomorphisms to spin groups.

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Matthias Wendt. 2017-04-25. On stably trivial spin torsors over low-dimensional schemes. https://arxiv.org/abs/1704.07768

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