I proved a theorem in number theory last week.

Don’t get me wrong; the theorem is fairly useless. The proof itself is trivial. But the fact that I came up with the proof, in my head, makes me proud…mostly because I’m a physicist, not a mathematician.

Here is the theorem:

**Square any odd integer greater than 1, and then subtract 1. The result is evenly divisible by 4.**

I’ll leave the proof to you, for fun. Do it in your head!

This is what theoretical physicists daydream about on 7 hour car rides.