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arXiv · 1501.03831

Square-Central and Artin-Schreier Elements in Division Algebras

Demba Barry·Adam Chapman
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Abstract

We study the behavior of square-central elements and Artin-Schreier elements in division algebras of exponent 2 and degree a power of 2. We provide chain lemmas for such elements in division algebras over 2-fields $F$ of cohomological $2$-dimension $\operatorname{cd}_2(F) \leq 2$, and deduce a common slot lemma for tensor products of quaternion algebras over such fields. We also extend to characteristic 2 a theorem proven by Merkurjev for characteristic not 2 on the decomposition of any central simple algebra of exponent 2 and degree a power of 2 over a field $F$ with $\operatorname{cd}_2(F) \leq 2$ as a tensor product of quaternion algebras.

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Demba Barry, Adam Chapman. 2015-04-13. Square-Central and Artin-Schreier Elements in Division Algebras. https://arxiv.org/abs/1501.03831

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