Paul J. Steinhardt is the Albert Einstein Professor in Science at Princeton University, where he is on the faculty of both the departments of Physics and Astrophysical Sciences. He cofounded and directs the Princeton Center for Theoretical Science. He has received the Dirac Medal and other prestigious awards for his work on the early universe and novel forms of matter. He is the author of The Second Kind of Impossible, and the coauthor of Endless Universe with Neil Turok, which describes the two competing ideas in cosmology to which he contributed. With his student, Dov Levine, Steinhardt first invented the theoretical concept of quasicrystals before they were synthesized in a laboratory. More than three decades later, with Luca Bindi, he guided the team that led to the discovery of three different natural quasicrystals in the Kamchatka Peninsula. In 2014, the International Mineralogical Association named a new mineral “steinhardtite” in his honor.