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arXiv · 1106.6312

Sur le groupe de Brauer transcendant

Jean-Louis Colliot-Thélène·Alexei N. Skorobogatov
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Abstract

For a smooth and projective variety X over a field k of characteristic zero we prove the finiteness of the cokernel of the natural map from the Brauer group of X to the Galois-invariant subgroup of the Brauer group of the same variety over an algebraic closure of k. Under further conditions on k, e.g. over number fields, we give estimates for the order of this cokernel. ---- Soit X une vari\'et\'e projective et lisse sur un corps k de caract\'eristique z\'ero. Le groupe de Brauer de X s'envoie dans les invariants, sous le groupe de Galois absolu de k, du groupe de Brauer de la m\^eme vari\'et\'e consid\'er\'ee sur une cl\^oture alg\'ebrique de k. Nous montrons que le quotient est fini. Sous des hypoth\`eses suppl\'ementaires, par exemple sur k un corps de nombres, nous donnons des estimations sur l'ordre de ce quotient.

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Jean-Louis Colliot-Thélène, Alexei N. Skorobogatov. 2011-06-30. Sur le groupe de Brauer transcendant. https://arxiv.org/abs/1106.6312

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