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arXiv · 1201.5310

Non-G-completely reducible subgroups of the exceptional algebraic groups

David I. Stewart
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Abstract

Let G be an exceptional algebraic group defined over an algebraically closed field k of characteristic p>0 and let H be a subgroup of G. Then following Serre we say H is G-completely reducible or G-cr if, whenever H is contained in a parabolic subgroup P of G, then H is in a Levi subgroup of that parabolic. Building on work of Liebeck and Seitz, we find all triples (X,G,p) such that there exists a closed, connected, simple non-G-cr subgroup H<G with root system X.

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David I. Stewart. 2012-04-24. Non-G-completely reducible subgroups of the exceptional algebraic groups. https://arxiv.org/abs/1201.5310

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