Overgroups of regular unipotent elements in simple algebraic groups
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- by Gunter Malle and Donna M. Testerman;
- Trans. Amer. Math. Soc. Ser. B 8 (2021), 788-822
- DOI: https://doi.org/10.1090/btran/72
- Published electronically: September 14, 2021
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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.References
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Bibliographic Information
- Gunter Malle
- Affiliation: FB Mathematik, TU Kaiserslautern, Postfach 3049, 67653 Kaiserslautern, Germany.
- MR Author ID: 225462
- Email: malle@mathematik.uni-kl.de
- Donna M. Testerman
- Affiliation: Institut de Mathématiques, Station 8, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
- MR Author ID: 265736
- Email: donna.testerman@epfl.ch
- Received by editor(s): June 23, 2020
- Received by editor(s) in revised form: January 9, 2021
- Published electronically: September 14, 2021
- Additional Notes: Donna Testerman is the corresponding author
Work on this article was begun while the authors were visiting the Mathematical Sciences Research Institute in Berkeley, California in Spring 2018 for the programme “Group Representation Theory and Applications” supported by the National Science Foundation under Grant No. DMS-1440140. The second author was supported by the Fonds National Suisse de la Recherche Scientifique grant number 200021-175571. We thank the Isaac Newton Institute for the Mathematical Sciences, where this work was completed, for support and hospitality during the programme “Groups, Representations and Applications: New Perspectives”. This work was supported by: EPSRC grant number EP/R014604/1. - © Copyright 2021 by the authors under Creative Commons Attribution-Noncommercial 3.0 License (CC BY NC 3.0)
- Journal: Trans. Amer. Math. Soc. Ser. B 8 (2021), 788-822
- MSC (2020): Primary 20G05, 20G07, 20E28
- DOI: https://doi.org/10.1090/btran/72
- MathSciNet review: 4312324