Categorical quotients for actions of groupoids on varieties
Abstract
For certain actions of the Weyl groupoid from [Sergeev and Veselov, Grothendieck rings of basic classical Lie superalgebras, Ann Math, 2011] on an affine variety , geometric properties of the map were studied in [Musson, On the geometry of some algebras related to the Weyl groupoid, Contemp. Math. 2024], In this paper we show that if the base field is uncountable, the map is a geometric quotient which is universal in the category of -schemes. To do this we adapt a result from [{Mumford}, {Fogarty}, {Kirwan}, {1994}], showing that a geometric quotient is universal in the category of -schemes, to quotients by groupoids and more generally by equivalence relations. In our approach a key role is played by the closed points and Jacobson schemes.
Keywords
Cite
@article{arxiv.2501.13510,
title = {Categorical quotients for actions of groupoids on varieties},
author = {Ian M. Musson},
journal= {arXiv preprint arXiv:2501.13510},
year = {2025}
}