OK, I'm showing my nerd shirt now, but one of the lines I really liked in John Scalzi's "Old Man's War" was when a character would say (and he said this several times), "I'd explain it to you, but you don't have the math." "The Black Hole War," by Leonard Susskind, will help you understand the math. Susskind's book is about Quantum Mechanics and Black Holes while Scalzi's books are science fiction, but Susskind made me think that I actually understood how things worked. So if you've finished Scalzi's series about John Watson, and think you want to understand the math, try "The Black Hole War."
Then, when you're finished with "The Black Hole War," try ""The Day We Found the Universe." And don't come crying back to me when you realize you've LEARNED something.