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arXiv · 1012.1782

Extention of Finite Solvable Torsors over a Curve

Marco Antei
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Abstract

Let $R$ be a discrete valuation ring with fraction field $K$ and with algebraically closed residue field of positive characteristic $p$. Let $X$ be a smooth fibered surface over $R$ with geometrically connected fibers endowed with a section $x\in X(R)$. Let $G$ be a finite solvable $K$-group scheme and assume that either $|G|=p^n$ or $G$ has a normal series of length 2. We prove that every quotient pointed $G$-torsor over the generic fiber $X_η$ of $X$ can be extended to a torsor over $X$ after eventually extending scalars and after eventually blowing up $X$ at a closed subscheme of its special fiber $X_s$.

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Marco Antei. 2010-12-08. Extention of Finite Solvable Torsors over a Curve. https://doi.org/10.1007/s00229-012-0535-4

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