A few days ago, I completed Walter Lewin's courses 8.01 (Newtonian Mechanics)and 8.02 (Electricity and Magnetism) . I loved the courses and I'm quite motivated to go further. I was thinking of two routes: a) Quantum Mechanics: I'll probably use Griffiths/Resnick/Shankar/Gasiorowicz. b) Special relativity: Probably Resnick. Which of the two routes should I choose, and what textbook should I use?