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arXiv · 1703.04055

Dynkin Diagrams and Short Peirce Gradings of Kantor Pairs

Bruce Allison·John Faulkner
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Abstract

In a recent article with Oleg Smirnov, we defined short Peirce (SP) graded Kantor pairs. For any such pair P, we defined a family, parameterized by the Weyl group of type BC_2, consisting of SP-graded Kantor pairs called Weyl images of P. In this article, we classify finite dimensional simple SP-graded Kantor pairs over an algebraically closed field of characteristic 0 in terms of marked Dynkin diagrams, and we show how to compute Weyl images using these diagrams. The theory is particularly attractive for close-to-Jordan Kantor pairs (which are variations of Freudenthal triple systems), and we construct the reflections of such pairs (with nontrivial gradings) starting from Jordan matrix pairs.

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Bruce Allison, John Faulkner. 2017-03-12. Dynkin Diagrams and Short Peirce Gradings of Kantor Pairs. https://arxiv.org/abs/1703.04055

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