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arXiv · 1012.1922

The second Stiefel-Whitney classes of l-adic cohomology

Takeshi Saito
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Abstract

For a proper smooth variety of even dimension over a field of characteristic different from 2 or l, the second Stiefel-Whitney class of the l-adic cohomology and the second Hasse-Witt class of the de Rham cohomology are both defined in the second Galois homology. We state a conjecture on their relation and give several evidences.

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Takeshi Saito. 2010-12-09. The second Stiefel-Whitney classes of l-adic cohomology. https://doi.org/10.1515/crelle-2012-0035

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