I think you should try to go back to school for physics. Or teach yourself physics. If this idea still draws you, you should do it.

What sub-field were you going for?

I majored in superconductivity

That's awesome! I've always been fascinated by superconductors, especially the so-called 'high temp' ones. There are some you can even make in a garage with a minimal setup. When I'm retired, maybe. :D