A Note on Fano Manifolds Whose Second Chern Character Is Positive A. J. De Jong and Jason Michael Starr
نویسنده
چکیده
Notation 1.1. Let X be a projective variety over an algebraically closed field. For every integer k ≥ 0, denote by Nk(X) the finitely-generated free Abelian group of k-cycles modulo numerical equivalence, and denote by N(X) the k graded piece of the quotient algebra A∗(X)/Num∗(X), cf. [Ful98, Example 19.3.9]. For every Z-module B, denote Nk(X)B := Nk(X)⊗B, resp. N(X)B := N(X)⊗B. Denote by NEk(X) ⊂ Nk(X) the semigroup generated by nonzero, effective k-cycles. For B a subring of R, denote by NEk(X)B the B>0-semigroup in Nk(X)B generated by NEk(X).
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