Effective potential and boundary conditions at r=0
PROFESSOR: There is an effective potential, as it's described here. Yes, there is a potential, the central force, but if there is angular momentum, it's like a centrifugal barrier. With angular momentum it becomes very difficult to reach the origin. Because if you want to reach the origin, you have to spin faster and faster. So it becomes very hard to reach the origin. And this is like a repulsive potential here. So you have an effective potential. You started with just a potential, the central potential, but that will become an effective potential. This whole thing in brackets over there is sometimes called the effective radial potential. And it's this V of r plus h squared over 2mr squared l times l plus 1. So if you have a Coulomb potential, that would try to make the electrons go all the way to the proton. This is attractive. Well, even that is not problematic for l equals 0. But for l different from 0, you have to add here a potential that diverges. And i...