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arXiv · 2208.13601

Pure semisimple and Köthe group rings

Samaneh Baghdari·Johan Öinert
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Abstract

In this article we provide a complete characterization of abelian group rings which are Köthe rings. We also provide characterizations of (possibly non-abelian) group rings over division rings which are Köthe rings, both in characteristic zero and in prime characteristic, and prove a Maschke type result for pure semisimplicity of group rings. Furthermore, we illustrate our results by several examples.

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Samaneh Baghdari, Johan Öinert. 2022-08-29. Pure semisimple and Köthe group rings. https://arxiv.org/abs/2208.13601

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