In your opinions, what are a list of books that encompass the frontiers of modern physics at this time. In other words, if you had to pick a set of books that would contain the knowledge to begin work on original and pressing matters in modern physics, what would it be. I'm also interested in particular math books that would be of importance for such books. For example, books on gauge theories, string theory, modern quantum field theories, attempts at quantum gravitation, cosmology. Books on lie theory, topology, geometry necessary for such studies etc etc. Your input is greatly appreciated.