He received a B.A. in physics from the University of Chicago in 1991, and a Ph.D. in physics from UC Berkeley in 1998. His thesis project,supervised by Professor Charles H. Townes, involved the development of adaptive optics for observing red giant stars. After graduation, he moved from astrophysics to biological physics, working as a postdoctoral fellow at the National Institutes of Health and teaching physics at George Washington University before coming to UCSB in 2003. With his coworkers at the NIH, he did some of the first experiments using single-molecule fluorescence to study protein folding, and pioneered the use of microfluidic mixing for single-molecule kinetics measurements. He continues to use ultra-sensitive light detection to make new measurements of the assembly and behavior of individual biological molecules.