Lisa Randall is an American theoretical physicist and a leading expert on particle physics and cosmology.

She works on several of the competing models of string theory in the quest to explain the fabric of the universe. Her best known contribution to the field is the Randall-Sundrum model, first published in 1999 with Raman Sundrum. She was the first tenured woman in the Princeton University physics department and the first tenured female theoretical physicist at both MIT and Harvard University.

Randall is an alumna of Hampshire College Summer Studies in Mathematics and graduated from Stuyvesant High School. She won first place in the Westinghouse Science Talent Search at the age of 18. Randall earned an AB at Harvard in 1983, and obtained her PhD in particle physics in 1987 under the direction of Howard Georgi. She was made a fellow of the American Academy of Arts and Sciences in 2004. Randall was featured in Newsweek magazine's "Who's Next" issue of January 2, 2006, as "one of the most promising theoretical physicists of her generation."

Randall studied particle physics and cosmology at Harvard University, where she is a professor of theoretical physics. Her research concerns elementary particles and fundamental forces, and has involved the study of a wide variety of models, the most recent involving extra dimensions of space. She has also worked on supersymmetry, Standard Model observables, cosmic inflation, baryogenesis, grand unified theories, general relativity. Randall's book Warped Passages: Unraveling the Mysteries of the Universe's Hidden Dimensions was included in the New York Times' 100 notable books of 2005.

Randall earned her PhD from Harvard University and held professorships at MIT and Princeton University before returning to Harvard in 2001. She is a member of the American Academy of Arts and Sciences and the National Academy of Sciences, a fellow of the American Physical Society, and is a past winner of an Alfred P. Sloan Foundation Research Fellowship, a National Science Foundation Young Investigator Award in 1992, a DOE Outstanding Junior Investigator Award, and the Westinghouse Science Talent Search. In 2003, she received the Premio Caterina Tomassoni e Felice Pietro Chisesi Award, from the Sapienza University of Rome. In autumn 2004, she was the most cited theoretical physicist of the previous five years. In 2006, she received the Klopsted Award from the American Association of Physics Teachers (AAPT). Professor Randall was featured in Seed magazine's “2005 Year in Science Icons ” and in Newsweek's “Who's Next in 2006”. She has helped organize numerous conferences and has been on the editorial board of several major theoretical physics journals.