English

Jacobson-Morozov Lemma for Algebraic Supergroups

Representation Theory 2026-01-22 v2

Abstract

Given a quasi-reductive algebraic supergroup GG, we use the theory of semisimplifications of symmetric monoidal categories to define a symmetric monoidal functor Φx:Rep(G)Rep(OSp(12))\Phi_x: Rep(G) \to Rep(OSp(1|2)) associated to any given element xLie(G)1ˉx \in \mathrm{Lie}(G)_{\bar 1}. For nilpotent elements xx, we show that the functor Φx\Phi_x can be defined using the Deligne filtration associated to xx. We use this approach to prove an analogue of the Jacobson-Morozov Lemma for algebraic supergroups. Namely, we give a necessary and sufficient condition on odd nilpotent elements xLie(G)1ˉx\in \mathrm{Lie}(G)_{\bar 1} which define an embedding of supergroups OSp(12)GOSp(1|2)\to G so that xx lies in the image of the corresponding Lie algebra homomorphism.

Keywords

Cite

@article{arxiv.2007.08731,
  title  = {Jacobson-Morozov Lemma for Algebraic Supergroups},
  author = {Inna Entova-Aizenbud and Vera Serganova},
  journal= {arXiv preprint arXiv:2007.08731},
  year   = {2026}
}

Comments

v2: fixed reference in Section 6

R2 v1 2026-06-23T17:11:09.111Z