{ "id": "2212.06022", "version": "v1", "published": "2022-12-12T16:41:41.000Z", "updated": "2022-12-12T16:41:41.000Z", "title": "Reduction by stages for finite W-algebras", "authors": [ "Naoki Genra", "Thibault Juillard" ], "comment": "30 pages, 4 figures", "categories": [ "math.RT", "math.AG", "math.QA" ], "abstract": "Let $\\mathfrak{g}$ be a semisimple Lie algebra: its dual space $\\mathfrak{g}^*$ is a Poisson variety. It is well known that for each nilpotent element $f$ in $\\mathfrak{g}^*$, it is possible to construct a new Poisson structure by Hamiltonian reduction which is isomorphic to some subvariety of $\\mathfrak{g}^*$, the Slodowy slice $S_f$. We prove that, given two nilpotent elements $f_1$ and $f_2$, with some assumptions, it is possible to perform a Hamiltonian reduction by stages: the slice $S_{f_2}$ is a Hamiltonian reduction of the slice $S_{f_1}$. We also state an analogue result in the setting of finite W-algebras, which are quantizations of Slodowy slices. As corollary in type A, we prove the conjecture of Morgan stating that any hook type W-algebra can be obtained as Hamiltonian reduction from any other hook type one. As an application, we establish a generalization of the Skryabin equivalence. Finally, we make some conjectures about a possible analogue of our results in the context of affine W-algebras.", "revisions": [ { "version": "v1", "updated": "2022-12-12T16:41:41.000Z" } ], "analyses": { "keywords": [ "finite w-algebras", "hamiltonian reduction", "slodowy slice", "nilpotent element", "hook type w-algebra" ], "note": { "typesetting": "TeX", "pages": 30, "language": "en", "license": "arXiv", "status": "editable" } } }