Spherical Nilpotent Orbits in Positive Characteristic

Russell Fowler; Gerhard Roehrle

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arXiv · 0708.0923

Spherical Nilpotent Orbits in Positive Characteristic

Russell Fowler·Gerhard Roehrle

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Abstract

Let G be a connected reductive linear algebraic group defined over an algebraically closed field of characteristic p. Assume that p is good for G. In this note we classify all the spherical nilpotent G-orbits in the Lie algebra of G. The classification is the same as in the characteristic zero case obtained by D.I. Panyushev in 1994: for e a nilpotent element in the Lie algebra of G, the G-orbit G.e is spherical if and only if the height of e is at most 3.

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BibTeX RIS

Russell Fowler, Gerhard Roehrle. 2008-05-27. Spherical Nilpotent Orbits in Positive Characteristic. https://arxiv.org/abs/0708.0923

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