A lorentz invariant or field theory approach.

洛伦兹不变量和场论步骤。

It's also  interesting to note that the physics of magnetic fields deflecting moving electrons, called the  Lorentz Force, is the driving principle behind all electric motors, just with coils of wires  and different configurations of magnetic fields.

同样有趣的是， 磁场偏转移动电子的物理原理，称为洛伦兹力， 是所有电动机背后的驱动原理，只需线圈和不同配置的磁场即可。