Clifford Cheung is a theoretical physicist at the California Institute of Technology. He received his B.S. from Yale University in 2004 and his Ph.D. in physics from Harvard University in 2009 before joining the faculty at Caltech. He is a recipient of an Early Career Research Award from the Department of Energy and is a fellow of the Alfred P. Sloan foundation.

Professor Cheung's research explores fundamental puzzles in particle physics, cosmology, and quantum field theory. This work makes contact with open questions regarding the origin and nature of dark matter as well as the properties of the nascent universe during cosmic inflation.  

Professor Cheung is also interested in the study of scattering amplitudes, which are fundamental observables encoding the dynamics of interacting particles. At a basic level, these efforts are dedicated to understanding why the laws of physics are as they are—in particular, discerning which aspects of the natural world are inevitable purely from consistency with basic physical principles.