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arXiv · 1305.5881

On the local-global principle for divisibility in the cohomology of elliptic curves

Brendan Creutz
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Abstract

For every prime power p^n with p = 2 or 3 and n > 1 we give an example of an elliptic curve over Q containing a rational point which is locally divisible by p^n but is not divisible by p^n. For these same prime powers we construct examples showing that the analogous local-global principle for divisibility in the Weil-Ch\^atelet group can also fail.

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Brendan Creutz. 2013-05-25. On the local-global principle for divisibility in the cohomology of elliptic curves. https://arxiv.org/abs/1305.5881

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