Thomas F. Rosenbaum, the California Institute of Technology's ninth president and professor of physics, came to Caltech in 2014 from the University of Chicago, where he most recently served as provost. Rosenbaum is an expert on the quantum mechanical nature of materials, best observed at temperatures near absolute zero. He conducted research at Bell Laboratories and at IBM Watson Research Center before he joined the University of Chicago faculty. Rosenbaum is an elected fellow of the American Physical Society, the American Association for the Advancement of Science, and the American Academy of Arts and Sciences.