Criteria for $\sigma $-ampleness
نویسندگان
چکیده
منابع مشابه
Criteria for Σ-ampleness
In the noncommutative geometry of Artin, Van den Bergh, and others, the twisted homogeneous coordinate ring is one of the basic constructions. Such a ring is defined by a σ-ample divisor, where σ is an automorphism of a projective scheme X. Many open questions regarding σ-ample divisors have remained. We derive a relatively simple necessary and sufficient condition for a divisor on X to be σ-am...
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The twisted homogeneous coordinate ring is one of the basic constructions of the noncommutative projective geometry of Artin, Van den Bergh, and others. Chan generalized this construction to the multi-homogeneous case, using a concept of right ampleness for a finite collection of invertible sheaves and automorphisms of a projective scheme. From this he derives that certain multi-homogeneous rin...
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ژورنال
عنوان ژورنال: Journal of the American Mathematical Society
سال: 2000
ISSN: 0894-0347,1088-6834
DOI: 10.1090/s0894-0347-00-00334-9