Cohomologie non ramifiée dans le produit avec une courbe elliptique

2018/02/12 by Colliot-Thélène, Jean-Louis
#14C30 14C25 14C35 19E15 #Algebraic Geometry (math.AG) #FOS: Mathematics

paper · doi:10.48550/arxiv.1802.04372

Abstract

A method of Gabber (2002) produces unramified cohomology classes in the products of certain varieties with an elliptic curve. The connection between third unramified cohomology and integral Hodge conjecture for codimension 2 cycles (2012, which builds upon results from algebraic K-Theory, then gives many examples of such a product for which this conjecture fails. The special case of the product with an Enriques surface was established by Benoist and Ottem (2018).

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