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arXiv · 1704.04072

Tores associ\'es \`a une alg\`ebre \'etale quartique

Jean-Pierre Tignol
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Abstract

Homomorphisms are defined between the multiplicative group of an etale algebra of dimension 4 and the multiplicative group of a canonically associated etale algebra of degree 6 over an arbitrary field. These homomorphisms are used to relate various norm groups and to describe the 2-torsion in the relative Brauer group of a separable extension of degree 4. Several remarkable properties of biquadratic extensions are thus extended to arbitrary etale algebras of dimension 4.

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Jean-Pierre Tignol. 2017-04-13. Tores associ\'es \`a une alg\`ebre \'etale quartique. https://doi.org/10.1016/j.jpaa.2017.02.016

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