If you’re craving some light reading, might I suggest Stephen Hawking’s 1965 doctoral thesis ” Properties of Expanding Universes .” In celebration of “Open Access Week 2017,” Cambridge University Library has made Hawking’s 117-page thesis freely available online. “By making my PhD thesis Open Access, I hope to inspire people around the world to look up at the stars and not down at their feet; to wonder about our place in the universe and to try and make sense of the cosmos,” Hawking says .