What is the branch of physics that concerns itself with relativity, quantum mechanics, etc.?

Would this be astrophysics? I can’t think of anything else.
Just curious because I find this kind of stuff really interesting, as you can probably tell by my username.

When u get past the level of Discovery Channel documentaries, it’s all pretty much just a lot of math.

I’m going into physics next year. While what you could described could go into theoretical astrophysics, “modern physics” is a much better term for these.

@GMTplus7 Haha that’s true, but I don’t mind math. Thanks!

@Anubis13 Hmm that’s what I was thinking, but is “modern physics” offered as a major? I know astrophysics is, but I haven’t heard of many modern physics majors.

Generally, the first 2 years of a physics major all students take similar classes. For example, a sequence of classes that included classical mechanics, thermodynamics, E&M, and “modern physics.” After that, you choose electives somewhat. The bigger choice is actually more whether you are aiming for experimental or theoretical physics. There are experimental physicists who also work with relativity and quantum mechanics; it’s not only theoretical.

Depends what college you got to. Most students would major in physics with a math minor, and would specialize at the graduate level. You’d take Modern Physics as a sophomore or a junior.
If you attend a flagship university honors program, you may be allowed to take graduate courses junior and senior year, and in addition to those some programs (Reed? Lawrence?) involve students closely into research.
Note that Applied Physics is where it’s at right now - fascinating research and incredible discoveries.