Brian Greene is a professor of Physics and Mathematics at Columbia University, and Director of Columbia’s Center for Theoretical Physics. He is recognized for a number of groundbreaking discoveries in mathematical physics and superstring theory. Professor Greene's books, The Elegant Universe, The Fabric of the Cosmos, The Hidden Reality, and Until the End of Time, have collectively spent 70 weeks on the New York Times bestseller list and sold over two million copies worldwide. Professor Greene is a frequent guest on late night television and was the host of two award-winning NOVA mini-series based on his books. He also wrote and performed in Light Falls, a live theatrical exploration of Einstein’s discoveries, that was broadcast nationally on PBS. Together with Tracy Day, Professor Greene co-founded the World Science Festival and serves as Chairman of the Board.