English

Invariant Hilbert schemes and desingularizations of symplectic reductions for classical groups

Algebraic Geometry 2013-12-24 v3 Symplectic Geometry

Abstract

Let GGL(V)G \subset GL(V) be a reductive algebraic subgroup acting on the symplectic vector space W=(VV)mW=(V \oplus V^*)^{\oplus m}, and let μ: WLie(G)\mu:\ W \rightarrow Lie(G)^* be the corresponding moment map. In this article, we use the theory of invariant Hilbert schemes to construct a canonical desingularization of the symplectic reduction μ1(0)/ ⁣/G\mu^{-1}(0)/\!/G for classes of examples where G=GL(V)G=GL(V), O(V)O(V), or Sp(V)Sp(V). For these classes of examples, μ1(0)/ ⁣/G\mu^{-1}(0)/\!/G is isomorphic to the closure of a nilpotent orbit in a simple Lie algebra, and we compare the Hilbert-Chow morphism with the (well-known) symplectic desingularizations of μ1(0)/ ⁣/G\mu^{-1}(0)/\!/G.

Keywords

Cite

@article{arxiv.1303.3032,
  title  = {Invariant Hilbert schemes and desingularizations of symplectic reductions for classical groups},
  author = {Ronan Terpereau},
  journal= {arXiv preprint arXiv:1303.3032},
  year   = {2013}
}

Comments

21 pages, final version, to appear in Math. Z