English

Gelfand-Cetlin abelianizations of symplectic quotients

Symplectic Geometry 2025-01-01 v1

Abstract

We show that generic symplectic quotients of a Hamiltonian GG-space MM by the action of a compact connected Lie group GG are also symplectic quotients of the same manifold MM by a compact torus. The torus action in question arises from certain integrable systems on g\mathfrak{g}^*, the dual of the Lie algebra of GG. Examples of such integrable systems include the Gelfand-Cetlin systems of Guillemin-Sternberg in the case of unitary and special orthogonal groups, and certain integrable systems constructed for all compact connected Lie groups by Hoffman-Lane. Our abelianization result holds for smooth quotients, and more generally for quotients which are stratified symplectic spaces in the sense of Sjamaar-Lerman.

Keywords

Cite

@article{arxiv.2209.04978,
  title  = {Gelfand-Cetlin abelianizations of symplectic quotients},
  author = {Peter Crooks and Jonathan Weitsman},
  journal= {arXiv preprint arXiv:2209.04978},
  year   = {2025}
}