Decomposition Varieties in Semisimple Lie Algebras
Canadian journal of mathematics, Tome 50 (1998) no. 5, pp. 929-971

Voir la notice de l'article provenant de la source Cambridge University Press

The notion of decompositon class in a semisimple Lie algebra is a common generalization of nilpotent orbits and the set of regular semisimple elements.We prove that the closure of a decomposition class has many properties in common with nilpotent varieties, e.g., its normalization has rational singularities.The famous Grothendieck simultaneous resolution is related to the decomposition class of regular semisimple elements. We study the properties of the analogous commutative diagrams associated to an arbitrary decomposition class.
DOI : 10.4153/CJM-1998-048-6
Mots-clés : 14L30, 14M17, 15A30, 17B45
Broer, Abraham. Decomposition Varieties in Semisimple Lie Algebras. Canadian journal of mathematics, Tome 50 (1998) no. 5, pp. 929-971. doi: 10.4153/CJM-1998-048-6
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