# Modules de cycles et classes non ramifi\'ees sur un espace classifiant

@article{Kahn2012ModulesDC,
title={Modules de cycles et classes non ramifi\'ees sur un espace classifiant},
author={Bruno Kahn and Ngan Thi Kim Nguyen},
journal={arXiv: Algebraic Geometry},
year={2012}
}
• Published 1 November 2012
• Mathematics
• arXiv: Algebraic Geometry
Let G be a finite group of exponent m and let k be a field of characteristic prime to m, containing the m-th roots of unity. For any Rost cycle module M over k, we construct exact sequences detecting the unramified elements in Serre's group of invariants of G with values in M in terms of "residue" morphisms associated to pairs (D,g), where D runs through the subgroups of G and g runs through the homomorphisms \mu_m \to G whose image centralises D. This allows us to recover results of Bogomolov…
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