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SINGULARITIES OF CLOSURES OF B-CONJUGACY CLASSES OF NILPOTENT ELEMENTS OF HEIGHT 2

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Abstract

We prove that for a simply laced group, the closure of the Borel conjugacy class of any nilpotent element of height 2 in its conjugacy class is normal and admits a rational resolution. We extend this, using Frobenius splitting techniques, to the closure in the whole Lie algebra if either the group has type A or the element has rank 2.

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Authors and Affiliations

  1. Bergische Universität Wuppertal, D-42097, Wuppertal, Germany

    M. BENDER

  2. Laboratoire de Mathématiques de Versailles, UVSQ, CNRS Université Paris-Saclay, 78035, Versailles, France

    N. PERRIN

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  1. M. BENDER
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  2. N. PERRIN
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Correspondence to M. BENDER.

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BENDER, M., PERRIN, N. SINGULARITIES OF CLOSURES OF B-CONJUGACY CLASSES OF NILPOTENT ELEMENTS OF HEIGHT 2. Transformation Groups 24, 741–768 (2019). https://doi.org/10.1007/s00031-018-9505-6

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  • DOI: https://doi.org/10.1007/s00031-018-9505-6

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