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Groupes fondamentaux motiviques de Tate mixte

P. Deligne·A. B. Goncharov
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Abstract

We define the category of mixed Tate motives over the ring of S-integers of a number field. We define the motivic fundamental group (made unipotent) of a unirational variety over a number field. We apply this to the study of the motivic fundamental group of the projective line punctured at zero, infinity and all N-th roots of unity.

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P. Deligne, A. B. Goncharov. 2003-02-27. Groupes fondamentaux motiviques de Tate mixte. https://arxiv.org/abs/math/0302267

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