A Comparison of Cohomological Obstructions to the Hasse Principle and to Weak Approximation

Yisheng Tian

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arXiv · 2211.02850

A Comparison of Cohomological Obstructions to the Hasse Principle and to Weak Approximation

Yisheng Tian

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Abstract

We show that certain Tate--Shafarevich groups are unramified which enables us to give an obstruction to the Hasse principle for torsors under tori over p-adic function fields.

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Yisheng Tian. 2022-11-05. A Comparison of Cohomological Obstructions to the Hasse Principle and to Weak Approximation. https://arxiv.org/abs/2211.02850

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