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arXiv · 1405.5991

Galois descent for the gonality of curves

Joaquim Roé·Xavier Xarles
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Abstract

We determine conditions for the invariance of the gonality under base extension, depending on the numeric invariants of the curve. More generally, we study the Galois descent of morphisms of curves to Brauer-Severi varieties, and also of rational normal scrolls.

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Joaquim Roé, Xavier Xarles. 2014-05-23. Galois descent for the gonality of curves. https://arxiv.org/abs/1405.5991

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