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arXiv · 2005.06996

Embeddings of maximal tori in classical groups and Hasse principles

Eva Bayer-Fluckiger
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Abstract

The aim of this note is to revisit the question of local-global principles for embeddings of etale algebras with involution into central simple algebras with involution over global fields of characteristic not 2. A necessary and sufficient condition is given in a joint paper with Tingyu Lee and Raman Parimala. In the present paper, we give a simpler description of the obstruction group. It is also shown that if the etale algebra is a product of pairwise independent field extensions, then the Hasse principle holds.

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Eva Bayer-Fluckiger. 2020-05-14. Embeddings of maximal tori in classical groups and Hasse principles. https://arxiv.org/abs/2005.06996

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