Obstructions to weak approximation for reductive groups over $p$-adic function fields

Yisheng Tian

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arXiv · 1904.05225

Obstructions to weak approximation for reductive groups over $p$-adic function fields

Yisheng Tian

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Abstract

We establish arithmetic duality theorems for short complexes associated to reductive groups over $p$-adic function fields. Using dualities, we deduce obstructions to weak approximation for certain reductive groups (especially quasi-split ones) and relate this obstruction to an unramified Galois cohomology group.

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Yisheng Tian. 2019-04-10. Obstructions to weak approximation for reductive groups over $p$-adic function fields. https://arxiv.org/abs/1904.05225

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