Sean Carroll is a theoretical physicist at the California Institute of Technology.  He received his Ph.D. in 1993 from Harvard University, and has previously worked at MIT, the Institute for Theoretical Physics at the University of California, Santa Barbara, and the University of Chicago.  His research ranges over a number of topics in theoretical physics, focusing on cosmology, particle physics, and general relativity, with special emphasis on dark matter, dark energy, and the origin of the universe.

He is the author of From Eternity to Here, a popular book on cosmology and the arrow of time, and of Spacetime and Geometry, a textbook on general relativity; has produced a set of introductory lectures for The Teaching Company entitled Dark Matter and Dark Energy: The Dark Side of the Universe; and is a co-founder of the popular science blog Cosmic Variance.