Projective embeddings of projective schemes blown up at subschemes
نویسندگان
چکیده
منابع مشابه
Embeddings of Projective Schemes Blown up at Subschemes
Suppose X is a nonsingular projective scheme, Z a nonsingular closed sub-scheme of X. Let˜X be the blowup of X centered at Z, E0 the pull-back of a general hyperplane in X, and E the exceptional divisor. In this paper, we study projective em-beddings of˜X given by divisors De,t = tE0 − eE. When X satisfies a necessary condition, we give explicit values of d and δ such that for all e > 0 and t >...
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Suppose X is a nonsingular arithmetically Cohen-Macaulay projective scheme, Z a nonsingular closed subscheme of X, and˜I the ideal sheaf of Z in X. Let˜X be the blowup of X along˜I, E0 the pull-back of a general hyperplane in X, and E the exceptional divisor. In this paper, we study projective embeddings of˜X given by the divisors De,t = tE0 − eE. We give explicit values of d and δ such that fo...
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ژورنال
عنوان ژورنال: Mathematische Zeitschrift
سال: 2004
ISSN: 0025-5874,1432-1823
DOI: 10.1007/s00209-003-0586-z