"[T]his is called the Standard Model Lagrangian, that curly \mathcal{L} at the start is for Lagrangian... and there's lots of different components of that. Now if I write it out in full, I get what is the most egotistical physics teacher in the entire world. So if I wrote it out in full... really you don't need to read it, I promise, all of the different terms in that equation describe an interaction between different types of particles and force carriers..."