Towards connectivity for codimension 2 cycles: Infinitesimal deformations
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چکیده
منابع مشابه
Towards Connectivity for Codimension 2 Cycles: Infinitesimal Deformations
Let X be a smooth projective variety over an algebraically closed field k ⊂ C of characteristic zero, and Y ⊂ X a smooth complete intersection. The Weak Lefschetz theorem states that the natural restriction map H(X(C), Q) → H(Y (C), Q) on singular cohomology is an isomorphism for all i < dim(Y ). The Bloch-Beilinson conjectures on the existence of certain filtrations on Chow groups combined wit...
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For a given sequence of integers (ni) ∞ i=1 we consider all the central simple algebras A (over all fields) satisfying the condition ind A = ni and find among them an algebra having the biggest torsion in the second Chow group CH of the corresponding Severi-Brauer variety (“biggest” means that it can be mapped epimorphically onto each other). We describe this biggest torsion in a way in general...
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Let Y be a smooth projective variety over C, and X be a smooth hypersurface in Y . We prove that the natural restriction map on Chow groups of codimension two cycles is an isomorphism when restricted to the torsion subgroups provided dimY ě 5. We prove an analogous statement for a very general hypersurface X Ă P of degree ě 5. In the more general setting of a very general hypersurface X of suff...
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ژورنال
عنوان ژورنال: Journal of Algebra
سال: 2014
ISSN: 0021-8693
DOI: 10.1016/j.jalgebra.2013.09.051