Ample Filters of Invertible Sheaves
نویسنده
چکیده
Let X be a scheme, proper over a commutative noetherian ring A. We introduce the concept of an ample filter of invertible sheaves on X and generalize the most important equivalent criteria for ampleness of an invertible sheaf. We also prove the Theorem of the Base for X and generalize Serre’s Vanishing Theorem. We then generalize results for twisted homogeneous coordinate rings which were previously known only when X was projective over an algebraically closed field. Specifically, we show that the concepts of left and right σ-ampleness are equivalent and that the associated twisted homogeneous coordinate ring must be noetherian.
منابع مشابه
Ample invertible sheaves on the irreducible components of an exceptional locus
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