Cosmologist and close collaborator of Stephen Hawking, Thomas Hertog discusses his book, On the Origin of Time: Stephen Hawking's Final Theory, a look at the intellectual superstar’s final thoughts on the cosmos. Hertog offers a striking new vision of the universe’s birth that will profoundly transform the way we think about our place in the order of the cosmos and may ultimately prove to be Hawking’s greatest legacy. Order Thomas Hertog's book now. Thomas Hertog is an internationally renowned cosmologist who was for many years a close collaborator of the late Stephen Hawking. He received his doctorate from the University of Cambridge and is currently professor of theoretical physics at the University of Leuven, where he studies the quantum nature of the big bang.