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arXiv · 1202.4714

The unramified Brauer group of norm one tori

Dasheng Wei
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Abstract

Let k be a number field and K/k Galois. We transform the construction of the unramified Brauer group of the norm one torus R^1_K/k(G_m) into the construction of a special abelian extension over K. If k=Q and K/Q biquadratic, we explicitly construct the unramified Brauer group of R^1_K/Q(G_m).

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Dasheng Wei. 2012-02-21. The unramified Brauer group of norm one tori. https://arxiv.org/abs/1202.4714

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