The national bestselling author of The God Equation takes us on a thrilling journey to explore black holes and time machines, multidimensional space and the possibility that parallel universes may lay alongside our own. “A wonderful tour, with an expert guide.” —Brian Greene, New York Times bestselling author of The Elegant Universe Kaku skillfully guides us through the latest innovations in string theory and its latest iteration, M-theory, which posits that our universe may be just one in an endless multiverse, a singular bubble floating in a sea of infinite bubble universes. If M-theory is proven correct, we may perhaps finally find answer to the question, “What happened before the big bang?” This is an exciting and unforgettable introduction into the new cutting-edge theories of physics and cosmology from one of the pre-eminent voices in the field.