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arXiv · 1202.2891

A descent map for curves with totally degenerate semi-stable reduction

Shahed Sharif
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Abstract

Let $K$ be a local field of residue characteristic $p$. Let $C$ be a curve over $K$ whose minimal proper regular model has totally degenerate semi-stable reduction. Under certain hypotheses, we compute the prime-to-$p$ rational torsion subgroup on the Jacobian of $C$. We also determine divisibility of line bundles on $C$, including rationality of theta characteristics and higher spin structures. These computations utilize arithmetic on the special fiber of $C$.

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Shahed Sharif. 2012-02-13. A descent map for curves with totally degenerate semi-stable reduction. https://arxiv.org/abs/1202.2891

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