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arXiv · 2506.01313

Surjectivity and flatness over DVR's (after Moret-Bailly)

Benedictus Margaux
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Abstract

We study morphisms of schemes $f : X \to S$ which are locally of finite type. We present conditions under which there exists a morphism $g : S'\to X$ of $S$--schemes such that $f \circ g $ is the canonical morphism $S'\to S$. Furthermore, we exhibit situations in which $f$ is flat surjective. Our results are mostly concerned with $S$ being the spectrum of a DVR.

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Benedictus Margaux. 2025-06-02. Surjectivity and flatness over DVR's (after Moret-Bailly). https://arxiv.org/abs/2506.01313

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