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arXiv · 0907.3586

Global descent obstructions for varieties

Jean-Marc Couveignes·Emmanuel Hallouin
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Abstract

We show how to transport descent obstructions from the category of covers to the category of varieties. We deduce examples of curves having $\QQ$ as field of moduli, that admit models over every completion of $\QQ$, but have no model over $\QQ$.

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Jean-Marc Couveignes, Emmanuel Hallouin. 2010-06-23. Global descent obstructions for varieties. https://doi.org/10.2140/ant.2011.5.431

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