A criterion for irreducibility of parabolic baby Verma modules of reductive Lie algebras

Autor: Yu-Feng Yao, Bin Shu, Yi-Yang Li
Rok vydání: 2020
Předmět:
Zdroj: Journal of Algebra. 563:111-147
ISSN: 0021-8693
Popis: Let $G$ be a connected, reductive algebraic group over an algebraically closed field $k$ of prime characteristic $p$ and $\mathfrak{g}=Lie(G)$. In this paper, we study representations of $\mathfrak{g}$ with a $p$-character $\chi$ of standard Levi form. When $\mathfrak{g}$ is of type $A_n, B_n, C_n$ or $D_n$, a sufficient condition for the irreducibility of standard parabolic baby Verma $\mathfrak{g}$-modules is obtained. This partially answers a question raised by Friedlander and Parshall in [Friedlander E. M. and Parshall B. J., Deformations of Lie algebra representations, Amer. J. Math. 112 (1990), 375-395]. Moreover, as an application, in the special case that $\mathfrak{g}$ is of type $A_n$ or $B_n$, and $\chi$ lies in the sub-regular nilpotent orbit, we recover a result of Jantzen in [Jantzen J. C., Subregular nilpotent representations of $sl_n$ and $so_{2n+1}$, Math. Proc. Cambridge Philos. Soc. 126 (1999), 223-257].
Comment: 16 pages. Minor revision and references added
Databáze: OpenAIRE