GINO SEGRE is a professor of Physics and Astronomy at the University of Pennsylvania. He was born in Florence, Italy and raised in Florence and New York City. He has been a visiting professor at M.I.T. and Oxford, chair of the Physics and Astronomy Department of the University of Pennsylvania from 1987 until 1992, and Director of Theoretical Physics at the National Science Foundation in 1995. He is the author of Ordinary Geniuses: Max Delbruck, george Gamow, and the Origins of Genomics and Big Band Cosmology; Faust in Copenhagen: A Struggle for the Soul of Physics; and A Matter of Degrees: What Temperature Reveals About the Past and Future of Our Species, Planet, and Universe.