Kernels of numerical pushforwards

Mihai Fulger; Brian Lehmann

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arXiv · 1407.6455

Kernels of numerical pushforwards

Mihai Fulger·Brian Lehmann

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Abstract

Let $π: X \to Y$ be a morphism of projective varieties and consider the pushforward map $π_*: N_k(X) \to N_k(Y)$ of numerical cycle classes. We show that when the Chow groups of points of the fibers are as simple as they can be, then the kernel of $π_*$ is spanned by k-cycles contracted by $π$.

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Mihai Fulger, Brian Lehmann. 2016-01-13. Kernels of numerical pushforwards. https://arxiv.org/abs/1407.6455

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