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arXiv · 2010.05275

On the coniveau of rationally connected threefolds

Claire Voisin
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Abstract

We prove that the integral cohomology modulo torsion of a rationally connected threefold comes from the integral cohomology of a smooth curve via the cylinder homomorphism associated to a family of $1$-cycles. Equivalently, it is of strong coniveau 1 in the sense of Benoist-Ottem.

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Claire Voisin. 2020-10-11. On the coniveau of rationally connected threefolds. https://doi.org/10.2140/gt.2022.26.2731

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