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arXiv · 1905.00445

Schur indices for noncommutative reality-based algebras with two nonreal basis elements

Allen Herman
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Abstract

This article discusses the representation theory of noncommutative algebras reality-based algebras with positive degree map over their field of definition. When the standard basis contains exactly two nonreal elements, the main result expresses the noncommutative simple component as a generalized quaternion algebra over its field of definition. The field of real numbers will always be a splitting field for this algebra, but there are noncommutative table algebras of dimension $6$ with rational field of definition for which it is a division algebra. The approach has other applications, one of which shows noncommutative association scheme of rank $7$ must have at least three symmetric relations.

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Allen Herman. 2019-05-01. Schur indices for noncommutative reality-based algebras with two nonreal basis elements. https://arxiv.org/abs/1905.00445

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