What don't we know about how electricity and/or magnetism works?
I want to start reading Griffiths electrodynamics during my holidays. But I am not sure of the math I need to know to start reading and understand the text thoroughly. So any advice would be ...
Is classical electromagnetism a dead research field? Are there any phenomena within classical electromagnetism that we have no explanation for?
I'm interested in the (very) low energy limit of quantum electrodynamics. I've seen that taking this limit does not yield Maxwell equations, but a quantum corrected non-linear version of them. If ...