A virtually ample field that is not ample
نویسندگان
چکیده
منابع مشابه
Ample Sheaves and Ample Families
1 Ample Sheaves Let X be a scheme and L an invertible sheaf. Given a global section f ∈ Γ(X,L ) the set Xf = {x ∈ X | germxf / ∈ mxLx} is open (MOS,Lemma 29). The inclusion Xf −→ X is affine (RAS,Lemma 6) and in particular if X is an affine scheme then Xf is itself affine. Given a sequence of global sections f1, . . . , fn the open sets Xfi cover X if and only if the fi generate L (MOS,Lemma 32...
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ژورنال
عنوان ژورنال: Israel Journal of Mathematics
سال: 2019
ISSN: 0021-2172,1565-8511
DOI: 10.1007/s11856-019-1934-y