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arXiv · 1506.07828

Principal bundles under reductive groups

Peter O'Sullivan
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Abstract

Let $k$ be a field of characteristic $0$. We consider principal bundles over a $k$-scheme with reductive structure group (not necessarily of finite type). It is showm in particular that for $k$ algebraically closed there exists on any complete connected $k$-scheme a universal such bundle. As a consequence, an explicit description of principal bundles with reductive structure group over curves of genus $0$ or $1$ is obtained.

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Peter O'Sullivan. 2015-06-25. Principal bundles under reductive groups. https://arxiv.org/abs/1506.07828

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