European incentive programs threatened to spin out of control when solar module prices dropped - decreasing producers' costs - while the rates utilities had to pay to buy that power stayed high.

VOA: standard.2010.03.23

But the reason that I like that analogy is that it points out a very important part of spin, and that's the idea that it's a description of the electron.

但我喜欢这个类比的原因是因为,它指出了自旋非常重要的一面，那就是它是一种电子的描述。

麻省理工公开课 - 化学原理课程节选