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arXiv · 2403.00159

Chow Künneth decomposition for étale motives

Ivan Rosas-Soto
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Abstract

In the present article we define an integral analogue of Chow-Künneth decomposition for étale motives. By using families of conservative functors we are able to establish a decomposition of the étale motive of commutative group schemes over a base and we relate to an integral étale Chow-Künneth decomposition of abelian varieties. For a projective variety $X$ of dimension $d$ over an algebraically closed field, we construct integral sub-motives $h^1_{\text{ét}}(X)$ and $h^{2d-1}_{\text{ét}}(X)$ of the motive $h_{\text{ét}}(X)$.

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Ivan Rosas-Soto. 2024-02-29. Chow Künneth decomposition for étale motives. https://arxiv.org/abs/2403.00159

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