When Milton instructs his muse, "Say first, for Heav'n hides nothing from thy view," there's something more here than the primary sense of the word, which is just "first in sequence."

弥尔顿写到缪斯的时候，“请先说，天界和地狱深渊在您的眼中，一切都了如指掌“,这句中“先“除了它本身的意思“最先“之外，还有其他的含义“

耶鲁公开课 - 弥尔顿课程节选

So if we say that l is just talking about our kinetic energy part, our rotational kinetic energy, and we know that electrons have potential energy, then it makes sense that l, in fact, can never go higher than n.

如果我们说，l仅仅是,描述动能项，我们的旋转动能，我们知道，电子有势能，所以可以理解，l不能比n高。

麻省理工公开课 - 化学原理课程节选