Frobenius Modules and De Jong’s Theorem
نویسندگان
چکیده
Let k be an algebraically closed field of characteristic p > 0. A theorem of de Jong shows that morphisms of modules over W (k)[[t]] with Frobenius and connection structure descend from the completion of W (k)((t)). A careful reading of de Jong’s proof suggests the possibility that an analogous theorem holds for modules with only a Frobenius structure. We show that this analogue holds in one natural formulation, but fails in a stronger formulation in which W (k)[[t]] is replaced by W (k[[t]]).
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