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arXiv · 2112.06077

Orbits of vectors in some representations. II

Igor Pevzner
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Abstract

Let $Φ$ be a root system of type $A_l$ or $D_l$. Let $K$ be a field of characteristic not $2$. Let $δ$ be the maximal root of $Φ$ and set $Φ_0 = \{α\inΦ; δ\perpα\}$. We describe orbits of the group $G_{\text{\rm sc}}(Φ_0, K)$ acting on the set $\langle e_α; \angle(α, δ) = π/3\rangle$.

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Igor Pevzner. 2021-12-11. Orbits of vectors in some representations. II. https://arxiv.org/abs/2112.06077

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