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arXiv · 1412.5654

Singularities of closures of spherical $B$-conjugacy classes of nilpotent orbits

Martin Bender·Nicolas Perrin
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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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Martin Bender, Nicolas Perrin. 2014-12-17. Singularities of closures of spherical $B$-conjugacy classes of nilpotent orbits. https://arxiv.org/abs/1412.5654

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