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Change of Coefficients for Drinfeld Modules, Shtuka, and Abelian Sheaves

Urs Hartl·Markus Hendler
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Abstract

We study the passage from Drinfeld-A'-modules to Drinfeld-A-modules for a given finite flat inclusion A \subset A'. We show that this defines a morphism from the moduli space of Drinfeld-A'-modules to the moduli space of Drinfeld-A-modules which is proper but in general not representable. For Drinfeld-Anderson shtuka and abelian sheaves instead of Drinfeld modules we obtain the same results.

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Urs Hartl, Markus Hendler. 2006-08-10. Change of Coefficients for Drinfeld Modules, Shtuka, and Abelian Sheaves. https://arxiv.org/abs/math/0608256

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