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arXiv · 1212.0552

On the Chow groups of the variety of lines of a cubic fourfold

Mingmin Shen·Charles Vial
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Abstract

Let $X$ be a smooth complex cubic fourfold and let $F$ be the variety of lines of $X$. The variety $F$ is known to be a smooth projective hyperkaehler fourfold, which is moreover endowed with a self rational map $\phi : F -\rightarrow F$ first constructed by C. Voisin. Here we define a filtration of Bloch--Beilinson type on the Chow group of zero-cycles $CH_0(F)$ which canonically splits under the action of $\phi$, thereby answering in this case a question of A. Beauville. Moreover, we show that this filtration is of motivic origin, in the sense that it arises from a Chow--Kuenneth decomposition of the diagonal.

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Mingmin Shen, Charles Vial. 2012-12-03. On the Chow groups of the variety of lines of a cubic fourfold. https://arxiv.org/abs/1212.0552

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