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arXiv · 1910.00449

On unit signatures and narrow class groups of odd degree abelian number fields

Benjamin Breen·Ila Varma·John Voight·appendix with Noam Elkies
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Abstract

For an abelian number field of odd degree, we study the structure of its 2-Selmer group as a bilinear space and as a Galois module. We prove structural results and make predictions for the distribution of unit signature ranks and narrow class groups in families where the degree and Galois group are fixed.

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Benjamin Breen, Ila Varma, John Voight, appendix with Noam Elkies. 2019-10-01. On unit signatures and narrow class groups of odd degree abelian number fields. https://arxiv.org/abs/1910.00449

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