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Sur la R-équivalence de torseurs sous un groupe fini

Laurent Moret-Bailly
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Abstract

We give criteria for R-equivalence of torsors under finite constant group schemes over a field. In paticular, using bitorsors, we obtain a Galois devissage result which formalises and generalises a theorem of Philippe Gille in the case of local fields; for instance, Gille's theorem is shown to extend to higher local fields.

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Laurent Moret-Bailly. 2002-09-25. Sur la R-équivalence de torseurs sous un groupe fini. https://arxiv.org/abs/math/0203151

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