The Importance of the Vector Potential

The vector potential is very, very important. It's the way that electricity and magnetism kind of get put into quantum mechanics. So when you're doing a lot of things like electromagnetic calculations, you just figure out what you want the potential to be at different points. But as far as controlling that vector potential, that I don't have any real idea how to do. All I really know how to do is put a current in a loop or put a magnet someplace. Those will make the magnetic field and then I can sort of figure out something like that vector potential based on that.