Edward Farhi

Work As a graduate student, Farhi introduced the jet variable thrust. He later worked with Leonard Susskind on grand unified theories with electro-weak dynamical symmetry breaking and with Larry Abbott at CERN on models in which quarks, leptons, and massive gauge bosons are composite. He and Robert Jaffe formalized a notion of strange matter and with Charles Alcock and Angela Olinto he studied "strange stars," compact objects made of strange matter. Later, he and Alan Guth studied limitations on creating a new inflationary universe in a laboratory. He and Guth, along with Sean Carroll, gave limitations on the existence of Gott time machines in two spatial dimensions.

Since the late '90s, Farhi has worked on quantum computing and quantum algorithms. He and Sam Gutmann, who have known each other since high school, introduced a continuous-time Hamiltonian-based approach to quantum computation. and proposed the first algorithms based on quantum walks. Along with Jeffrey Goldstone and Michael Sipser, they introduced an early proposal for adiabatic quantum computation. In 2007, Farhi, Goldstone, and Gutmann gave a polynomial quantum speedup, using quantum walks, for solving a certain combinatorial game. In 2010, along with Peter Shor and three others at MIT, he introduced a scheme for quantum money. In 2014 Farhi, Goldstone, and Gutmann introduced the quantum approximate optimization algorithm (QAOA) for finding approximate solutions to combinatorial search problems, which as of 2024 was viewed as a leading candidate to run on contemporary noisy intermediate-scale quantum devices. Farhi and Aram Harrow have argued that the lowest depth version of the QAOA could exhibit a form of quantum supremacy.