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arXiv · 1206.2420

Locally trivial torsors that are not Weil-Châtelet divisible

Brendan Creutz
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Abstract

For every prime p we give infinitely many examples of torsors under abelian varieties over Q that are locally trivial but not divisible by p in the Weil-Châtelet group. We also give an example of a locally trivial torsor under an elliptic curve over Q which is not divisible by 4 in the Weil-Châtelet group. This gives a negative answer to a question of Cassels.

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Brendan Creutz. 2012-09-21. Locally trivial torsors that are not Weil-Châtelet divisible. https://doi.org/10.1112/blms%2Fbdt019

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