I know this is a rather new field of research and that I may seem rather silly for asking, but I would like to know besides upper divison undergrad quantum mechanics ( which I've already studied ), what other subjects should I learn to get the basic background for researching quantum computers. Physics and especially quantum mechanics is an interesting subject, in which I've felt that I've learn so much yet I cannot see how I would even apply it to creating qubits. My understanding of quantum mechanics goes as far as pertubation and such, but that is about it. Also, what other types of math should I learn, possibly topology or differential geometry? I'm guessing Quantum Field Theory, Atomic Physics, and Quantum Electro Dynamics would be the next theories I might want to learn. But then again I don't want to waste my time picking up on things that are useless. I am ofcourse infinnetly ignorant so please educate me. Oh, and telling me I'm crazy isn't going to keep me from learning.