LEONARD MLODINOW received his PhD in theoretical physics from the University of California, Berkeley, was an Alexander von Humboldt fellow at the Max Planck Institute, and was on the faculty of the California Institute of Technology. His previous books include the best sellers The Grand Design and A Briefer History of Time (both with Stephen Hawking), Subliminal (winner of the PEN/E. O. Wilson Literary Science Writing Award), The Drunkard's Walk, and Elastic.