arXivDaily arXiv每日学术速递 周一至周五更新
北美退伍军人节(Veterans Day),12 日无更新
arXiv 0903.0398math.RT
收藏

关于$\mathfrak{sl}_2$主子代数的Dynkin指标

On the Dynkin index of a principal $\mathfrak{sl}_2$-subalgebra

Dmitri I. Panyushev

摘要:

设$g$是特征为零的代数闭域上的单李代数.本文的目的是证明$g$的一个主子$sl_2$-代数的Dynkin指标的一个闭公式。证明的关键步骤使用了弗赖登塔尔-德弗里斯的“奇怪公式”。作为应用,我们(1)计算了任意简单$g$ -模的Dynkin指数,(2)得到了连接$g$的指数与$g$的对偶Coxeter数和Langlands对偶$g^\vee$的对偶Coxeter数的恒等式.

英文摘要:

Let $g$ be a simple Lie algebra over an algebraically closed field of characteristic zero. The goal of this note is to prove a closed formula for the Dynkin index of a principal $sl_2$-subalgebra of $g$. The key step in the proof uses the "strange formula" of Freudenthal--de Vries. As an application, we (1) compute the Dynkin index any simple $g$-module regarded as $sl_2$-module and (2) obtain an identity connecting the exponents of $g$ and the dual Coxeter numbers of both $g$ and the Langlands dual $g^\vee$.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑