Symmetric pairs and associated commuting varieties

Abstract

AbstractLet $\g=\g_0\oplus\g_1$ be a $\mathbb Z_2$-grading of a simple Lie algebra $\g$. The commuting variety associated with such a grading is the variety of pairs of commuting elements from $\g_1$. We study the problem of irreducibility of these varieties. Using invariant-theoretic technique, we present new instances of reducible and irreducible commuting varieties.