Purity of the Stratification by Newton Polygons
نویسنده
چکیده
In this paper we prove four theorems: one on surface singularities, two on F crystals, and one on moduli of p-divisible groups. The reason we put together these results in one paper is that the proofs, as given here, show how these theorems are related. Let us first describe our results. Let (S, 0) be a normal surface singularity over an algebraically closed field of characteristic p. Let S̃ → S be a resolution of singularities. Our first result is Theorem 3.2: (1) Any Qp-cohomology class on the link of the singularity extends to the resolution, more precisely
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تاریخ انتشار 1999