CHRISTOPHE GALFARD holds a Ph.D. in theoretical physics from Cambridge University, where he was Professor Stephen Hawking s graduate student from 2000 to 2006. He now devotes his time to spreading modern scientific knowledge to the general public in entertaining ways, in France and in Europe, giving talks to more than 50,000 people and is a regular contributor to French TV and radio shows. Galfard has written four YA novels about science, and was co-author with Stephen Hawking and his daughter on their first YA novel, "George's Secret Key to the Universe."