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Künneth projectors for open varieties

Spencer Bloch·Hélène Esnault
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Abstract

We consider correspondences on smooth quasiprojective varieties $U$. An algebraic cycle inducing the Künneth projector onto $H^1(U)$ is constructed. Assuming normal crossings at infinity, the existence of relative motivic cohomology is shown to imply the independence of $\ell$ for traces of open correspondences.

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Spencer Bloch, Hélène Esnault. 2005-02-27. Künneth projectors for open varieties. https://arxiv.org/abs/math/0502447

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