I'm asking this to help with making subject choices. One thing I'd like carry away from this degree is an overall understanding of the origin and structure of the universe. I'm wondering how much quantum mechanics and quantum field theory should I take to gain this understanding. I have heard of quantum cosmology but I've no idea how influential/essential it is to the big picture and the level of QM it involves. There's only so much classes I can take so I want to know what's crucial and what's not. BTW, I don't intend work in cosmology or astrophysics, I just want to know it.