How do courses work in graduate school? I'm in undergrad right now and even though I am a physics major, I am mostly free to take whatever class I want to. However, I know in graduate school one is supposed to be becoming more specialized so how does taking non-physics classes work in graduate school? Also, if I'm interested in particle physics, what courses can I look forward to taking? I am asking this question because I am also quite interested in math and CS, and would be willing to take graduate level courses in these classes (primarily math) in order to understand and apply the physics I learn. Will I have time to take math classes/other electives in graduate school? Or will I just be too busy?