Martin Karplus, 1930–, Austrian-American theoretical chemist, b. Vienna, Ph.D. California Institute of Technology, 1953. He has been a professor at Harvard since 1967, studying the electronic structure, geometry, and dynamics of molecules. Karplus, with Michael Levitt and Arieh Warshel, received the Nobel Prize in Chemistry in 2013 for the developing multiscale models for complex chemical systems. In the 1960s and 70s, when others were modeling molecules using plastic balls and sticks, the trio (with Warshel working at times with Levitt and at other times with Karplus) began to develop computer simulations to elucidate the mechanisms underlying rapidly occurring complex chemical reactions like combustion and photosynthesis. To minimize the amount of computing power needed, their programs used classical physics to track the movement of atoms and quantum physics to describe how chemical bonds break and form.