On a Stratification of the Moduli of K3 Surfaces
نویسندگان
چکیده
In this paper we give a characterization of the height of K3 surfaces in characteristic p > 0. This enables us to calculate the cycle classes of the loci in families of K3 surfaces where the height is at least h. The formulas for such loci can be seen as generalizations of the famous formula of Deuring for the number of supersingular elliptic curves in characteristic p. In order to describe the tangent spaces to these loci we study the first cohomology of higher closed forms.
منابع مشابه
Formal Brauer groups and the moduli of abelian surfaces
Let X be an algebraic surface over an algebraically closed field k of characteristic p > 0. We denote by ΦX the formal Brauer group of X and by h = h(ΦX) the height of ΦX . In a previous paper, [6], we examined the structure of the stratification given by the height h in the moduli space of K3 surfaces, and we determined the cohomology class of each stratum. In this paper, we apply the methods ...
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