The closure diagram for nilpotent orbits of the split real form of 𝐸₇

Đoković, Dragomir

doi:10.1090/S1088-4165-01-00124-8

The closure diagram for nilpotent orbits of the split real form of ${E_7}$
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by Dragomir Ž. Đoković PDF

Represent. Theory 5 (2001), 284-316 Request permission

Abstract:

Let $\mathcal {O}_1$ and $\mathcal {O}_2$ be adjoint nilpotent orbits in a real semisimple Lie algebra. Write $\mathcal {O}_1\geq \mathcal {O}_2$ if $\mathcal {O}_2$ is contained in the closure of $\mathcal {O}_1.$ This defines a partial order on the set of such orbits, known as the closure ordering. We determine this order for the split real form E V of $E_7.$

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