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arXiv · 1504.07305

Relative Brauer groups of torsors of period two

Brendan Creutz
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Abstract

We consider the problem of computing the relative Brauer group of a torsor of period 2 under an elliptic curve E. We show how this problem can be reduced to finding a set of generators for the group of rational points on E. This extends work of Haile and Han to the case of torsors with unequal period and index. Several numerical examples are given.

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Brendan Creutz. 2015-04-27. Relative Brauer groups of torsors of period two. https://doi.org/10.1016/j.jalgebra.2016.03.034.

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