The Kepler Problem (Part 11)

In Part 9 we saw, loosely speaking, that the theory of a hydrogen atom is equivalent to the theory of a massless left-handed spin-½ particle in the Einstein universe—a static universe where space is a 3-sphere. Today we’ll ‘second quantize’ both of these equivalent theories and get new theories that again are equivalent.

‘Second quantization’ is a funny term. It’s a completely systematic way to get a new quantum theory from an old one. When you second quantize the theory of some particle, ...