I’ve posted a new article in the physics for mathematicians series. It gives an overview of classical electromagnetism from several perspectives, showing how the electromagnetic field strength can be thought of as the curvature of a connection on a principal bundle. It closes with a (very) brief discussion of classical Yang-Mills theory, which is a natural generalization of this idea and provides the template for almost all of the interactions in the Standard Model of particle physics.
This article is going up in a rougher state than some of the earlier ones. If you notice a problem or you just dislike the presentation of some or all of it, please shoot me an e-mail; I’d love to hear from you.
I’m still working hard on this series; I expect to keep pumping out articles in it until I get bored, which hasn’t happened yet! My current plan is to start work on a piece about statistical mechanics and thermodynamics next, but if anyone happens to be reading this and would like to see something else first, let me know!