All Questions
Tagged with picard-group neron-models
4 questions
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Does a line bundle on a normal Noetherian algebraic space come from a Weil divisor?
Let $X$ be a normal Noetherian algebraic space and $\mathscr{L}$ a line bundle on $X$. If $X$ is a scheme, then there is locally principal Weil divisor on $X$ that gives rise to $\mathscr{L}$. Is the ...
9
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1
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491
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Does a semistable curve descend to a regular base?
Let $f\colon X \rightarrow S$ be a semistable curve of genus $g \ge 0$. Being a semistable curve means that $f$ is a morphism of schemes such that
$f$ is proper, flat, and of finite presentation;
The ...
4
votes
1
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430
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Jacobian of a semistable curve
My question is about the proof of Example 8 in section 9.2 of the book "Neron models." There we have a semistable curve $X$ over an algebraically closed field $K$ and we let $\pi\colon \widetilde{X} \...
3
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1
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644
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Fiberwise vanishing of $H^2$ and formal smoothness of the Picard functor
My question is about the proof of 8.4/2 in "Neron models." The claim is that if $f\colon X \rightarrow S$ is a proper flat morphism of finite presentation such that $H^2(X_s, \mathscr{O}_{X_s}) = 0$ ...