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arXiv · 2601.00052

Vertical unramified Brauer groups of Galois normic bundles

Yufan Liu
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Abstract

We compute the vertical unramified Brauer group of the Galois normic bundles, which are given by $\mathrm{N}_{K/k}(\mathbf{z})=P(x)$. Our main result gives combinatorial formulas for the vertical unramified Brauer groups in terms of the Galois group structure of $K/k$ and the irreducible factors of $P(x)$.

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Yufan Liu. 2025-12-31. Vertical unramified Brauer groups of Galois normic bundles. https://doi.org/10.1016/j.jnt.2026.06.011

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