English

Quasi-connected reductive groups

Group Theory 2021-10-12 v2 Algebraic Geometry Representation Theory

Abstract

We introduce the notion of a quasi-connected reductive group over an arbitrary field to be an almost direct product of a connected semisimple group and a quasi-torus (a smooth group of multiplicative type). We show that a linear algebraic group is quasi-connected reductive if and only if it is isomorphic to a smooth normal subgroup of a connected reductive group.

Keywords

Cite

@article{arxiv.2108.05694,
  title  = {Quasi-connected reductive groups},
  author = {Mikhail Borovoi and Andrei A. Gornitskii and Zev Rosengarten},
  journal= {arXiv preprint arXiv:2108.05694},
  year   = {2021}
}

Comments

Withdrawn because it is superseded by the version 2 of arXiv:2103.04654 [math.RT] by the same authors