English

On symplectic resolutions and factoriality of Hamiltonian reductions

Algebraic Geometry 2019-04-25 v2 Representation Theory

Abstract

Recently, Herbig--Schwarz--Seaton have shown that 33-large representations of a reductive group GG give rise to a large class of symplectic singularities via Hamiltonian reduction. We show that these singularities are always terminal. We show that they are Q\mathbb{Q}-factorial if and only if GG has finite abelianization. When GG is connected and semi-simple, we show they are actually locally factorial. As a consequence, the symplectic singularities do not admit symplectic resolutions when GG is semi-simple. We end with some open questions.

Keywords

Cite

@article{arxiv.1809.04301,
  title  = {On symplectic resolutions and factoriality of Hamiltonian reductions},
  author = {Gwyn Bellamy and Travis Schedler},
  journal= {arXiv preprint arXiv:1809.04301},
  year   = {2019}
}

Comments

9 pages. The article has been updated to reflect the changes made by Herbig-Schwarz-Seaton to their article "Symplectic quotients have symplectic singularities" arXiv, 1706.02089