I've made a very special case that this is the case of an equally-weighted portfolio.

在这里我假设了一个特例,即一个各项资产权重相等的投资组合。

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You don't need to know those, but just because it's a special case with the hydrogen atom, they do tend to be named -- the most important, of course, tends to be the Balmer series because that's what we can actually see being emitted from the hydrogen atom.

你们不需要记住,但因为这是氢原子的特例,人们想要命名它，最重要的是当然是Balmer系,因为它是我们可以看到的,从氢原子放出来的光谱。

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