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arXiv · 2302.06069

Duality for cohomology of split tori on curves over local fields

Amalendu Krishna·Jitendra Rathore·Samiron Sadhukhan
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Abstract

We prove duality theorems for the {\'e}tale cohomology of logarithmic Hodge-Witt sheaves and split tori on smooth curves over a local field of positive characteristic. As an application, we obtain a description of the Brauer group of the function fields of curves over local fields in terms of the characters of the idele groups. We also show that the classical Brauer-Manin pairing between the Brauer and Picard groups of smooth projective curves over local fields has analogues for arbitrary smooth curves, smooth projective curves with modulus and singular projective curves over such fields.

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Amalendu Krishna, Jitendra Rathore, Samiron Sadhukhan. 2023-02-13. Duality for cohomology of split tori on curves over local fields. https://arxiv.org/abs/2302.06069

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