They then compare this spectrum with a theory, based on calculations from first principles, of how magnetic fields effect light emitted by hydrogen.

然后，他们把测得的光谱与理论计算得到的结果进行了比较，这种理论是基于氢怎样产生磁场效应区域的第一原则得到的。

You don't have to. You two have some strange force field effect on each other.

你没必要说 你们俩之间有一种奇怪的作用力场 会令你们互相影响。