Gorenstein Models of Del Pezzo Surfaces of Degree 1 over Dedekind Schemes
نویسنده
چکیده
Abstract. Let R be a Dedekind scheme, η its generic point, X and V del Pezzo surfaces of degree 1 over R that are Gorenstein Mori fiber spaces (as 3-folds germs over the ground field). We study birational maps φ : X 99K V over R which are isomorphisms over the generic point of R. We put down normal forms of such transformations (in suitable coordinates) and give some properties of X and V . In particular, we prove the uniqueness of a smooth model (corollary 3.2).
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تاریخ انتشار 2000