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Inverse-closed additive subgroups of fields

Sandro Mattarei
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Abstract

We describe the additive subgroups of fields which are closed with respect to taking inverses. In particular, in characteristic different from two any such subgroup is either a subfield or the kernel of the trace map of a quadratic subextension of the field.

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Sandro Mattarei. 2005-11-22. Inverse-closed additive subgroups of fields. https://arxiv.org/abs/math/0511538

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