Christophe Galfard received a doctorate in physics from the University of Cambridge under the tutelage of Stephen Hawking himself. He likes to say that he still has the shirt he wore when he was investigating black holes with him, although he has long since abandoned the more closed academic field to accompany the general public by the mysteries of the universe. Since then he has become the most brilliant and rigorous young popularizer of the moment, alternating lively lectures, appearances on television programs and feeding direct conversation with his readers through his website (especially in the section "Ask me about the universe" ). With that spirit he has published three novels and also helped his teacher and daughter Lucy Hawking write a successful youth novel, bestseller of The New York Times and translated into 45 languages. All their concerns and desires have been condensed in the titanic but accessible The universe in your hand, a book in which two things are proposed: use a single equation (E = mc2) and do not leave any reader behind. And he has achieved it by far: Blackie Books presents an international publishing phenomenon, considered the best scientific book of 2015 in France.