Hi All, I am currently undergoing independent study in quantum mechanics with Zettili's "Quantum Mechanics: Application and Concepts" and would like to know some good books for independent study for the "next level". My ultimate goal is to end up on the forefront of physics in terms of grand unification\cosmology. I am almost done with Zettili's book and found it to be extrodinarily clear and understandable ( as much as one can understand QM). On the other side of the spectrum, I am using RWT Gravitation and Schultz GR for general relativity (I already have Wald's book, but I am saving that for later because I know it's far too advanced for me at this time). So, can anyone point me in the direction of the books I need for the next "levels". If the book is not self contained (there are mathematical subjects that aren't covered thoroughly enough for a self-learner, please suggest a book that I can fill in the missing parts with). I am guessing I need a good book on QED next, but I am not sure how to fill the gap between QED\RWT and something on the level of QFT\Wald.