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arXiv · 1303.0651

Fine gradings and gradings by root systems on simple Lie algebras

Alberto Elduque
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Abstract

Given a fine abelian group grading on a finite dimensional simple Lie algebra over an algebraically closed field of characteristic zero, with universal grading group $G$, it is shown that the induced grading by the free group $G/\tor(G)$ is a grading by a (not necessarily reduced) root system. Some consequences for the classification of fine gradings on the exceptional simple Lie algebras are drawn.

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Alberto Elduque. 2013-03-04. Fine gradings and gradings by root systems on simple Lie algebras. https://arxiv.org/abs/1303.0651

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