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arXiv · 1401.7854

Describing units of integral group rings up to commensurability

Florian Eisele·Ann Kiefer·Inneke Van Gelder
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Abstract

We restrict the type of $2 \times 2$-matrices which can occur as simple components in the Wedderburn decomposition of the rational group algebra of a finite group. This results in a description up to commensurability of the group of units of the integral group ring $\mathbb Z G$ for all finite groups $G$ that do not have a non-commutative Frobenius complement as a quotient.

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Florian Eisele, Ann Kiefer, Inneke Van Gelder. 2014-09-17. Describing units of integral group rings up to commensurability. https://arxiv.org/abs/1401.7854

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