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arXiv · 2608.02141

Comparing local-global obstructions on algebraic stacks

Chang Lv·Han Wu·Xucheng Zhang
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Abstract

Let k be a number field. For quotient stacks [X/G] with X a smooth quasi-projective geometrically integral k-variety and G a linear k-group, we extend several relations between local-global obstructions previously known for varieties, showing that \'etale-Brauer obstruction is the finest among various obstructions (such as iterated descent, finite descent, descent, Brauer-Manin).

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Chang Lv, Han Wu, Xucheng Zhang. 2026-08-03. Comparing local-global obstructions on algebraic stacks. https://arxiv.org/abs/2608.02141

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