Overgroups of regular unipotent elements in simple algebraic groups

Malle, Gunter; Testerman, Donna

doi:10.1090/btran/72

Overgroups of regular unipotent elements in simple algebraic groups
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by Gunter Malle and Donna M. Testerman HTML | PDF

Trans. Amer. Math. Soc. Ser. B 8 (2021), 788-822

Abstract:

We investigate positive-dimensional closed reductive subgroups of almost simple algebraic groups containing a regular unipotent element. Our main result states that such subgroups do not lie inside proper parabolic subgroups unless possibly when their connected component is a torus. This extends the earlier result of Testerman and Zalesski treating connected reductive subgroups.

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