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arXiv · 1709.01170

The unramified Brauer group of homogeneous spaces with finite stabilizer

Giancarlo Lucchini Arteche
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Abstract

We give formulas for calculating the unramified Brauer group of a homogeneous space $X$ of a semisimple simply connected group $G$ with finite geometric stabilizer $\bar F$ over a wide family of fields of characteristic 0. When $k$ is a number field, we use these formulas in order to study the Brauer-Manin obstruction to the Hasse principle and weak approximation. We prove in particular that the Brauer-Manin pairing is constant on $X(k_v)$ for every $v$ outside from an explicit finite set of non archimedean places of $k$.

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Giancarlo Lucchini Arteche. 2017-09-04. The unramified Brauer group of homogeneous spaces with finite stabilizer. https://arxiv.org/abs/1709.01170

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