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arXiv · 1208.6359

Local-global principles for Galois cohomology

David Harbater·Julia Hartmann·Daniel Krashen
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Abstract

This paper proves local-global principles for Galois cohomology groups over function fields $F$ of curves that are defined over a complete discretely valued field. We show in particular that such principles hold for $H^n(F, Z/mZ(n-1))$, for all $n>1$. This is motivated by work of Kato and others, where such principles were shown in related cases for $n=3$. Using our results in combination with cohomological invariants, we obtain local-global principles for torsors and related algebraic structures over $F$. Our arguments rely on ideas from patching as well as the Bloch-Kato conjecture.

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David Harbater, Julia Hartmann, Daniel Krashen. 2012-08-31. Local-global principles for Galois cohomology. https://arxiv.org/abs/1208.6359

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