And, in any arbitrary crucible full of molten silver, half of them are going to be spin-up and half of them are going to be spin-down.

并且，在任一个浇满了熔银的坩埚中，银原子中的电子一半是向上转,另一半是向下转。

麻省理工公开课 - 固态化学导论课程节选

So this one is spin-up plus a half, this is spin-down minus a half.

所以自旋向上是正二分之一，而自旋向下是负二分之一。

麻省理工公开课 - 固态化学导论课程节选