CONNECTIONS, CURVATURE, AND p-CURVATURE
نویسنده
چکیده
1.1. Connections and derivations. Let S be a scheme, and X smooth and finite type over S throughout. We have the rank-n vector bundle ΩX/S of 1-forms on X over S. We also fix some notation in the case that S is of characteristic p: in this case, we denote by FT the absolute Frobenius map for any scheme T , by X = X×S S the p-twist of X over S, where the map used in the fiber product is FS : S → S, and F : X → X (p) the relative Frobenius map. We will also consider OX(p) as a sub-module of OX , identified with the kernel of d : OX → Ω 1 X/S.
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