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arXiv · 1511.07072

The derived functors of unramified cohomology

Bruno Kahn·R. Sujatha
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Abstract

We study the first "derived functors of unramified cohomology" in the sense of arXiv:1506.08385 [math.AG], applied to the sheaves $\mathbf{G}_m$ and $\mathcal{K}_2$. We find interesting connections with classical cycle-theoretic invariants of smooth projective varieties, involving notably a version of the Griffiths group, and the indecomposable $(2,1)$-cycles.

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Bruno Kahn, R. Sujatha. 2015-11-22. The derived functors of unramified cohomology. https://arxiv.org/abs/1511.07072

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