John Preskill
Richard P. Feynman Professor of Theoretical Physics
California Institute of Technology

John Preskill is the Richard P. Feynman Professor of Theoretical Physics at the California Institute of Technology, and Director of the Institute for Quantum Information and Matter at Caltech.

Preskill received his A.B. degree in physics in 1975 from Princeton University, and his Ph.D. in physics in 1980 from Harvard University, where he was a student of Steven Weinberg. He was a Junior Fellow in the Harvard Society of Fellows and Associate Professor of Physics at Harvard before joining the Caltech faculty in 1983. He became the John D. MacArthur Professor in 2002, and the Richard P. Feynman Professor of Theoretical Physics in 2010.

Until the mid-1990s, Preskill’s research focused on elementary particles, cosmology, and gravitation. He pointed out that superheavy magnetic monopoles should have been copiously produced in the very early universe, precipitating a crisis in theoretical cosmology that led to the inflationary universe proposal. With Mark Wise and Frank Wilczek, he explored the cosmological implications of the axion, a very light and weakly interacting hypothetical particle, and proposed that axions may comprise the cold dark matter of the universe. With Lawrence Krauss, he formulated the theory of local discrete symmetries, and with Sidney Coleman and Wilczek he developed the theory of quantum hair on black holes, which is classically invisible but has calculable quantum effects. With Hoi-Kwong Lo and others, he developed the theory of indistinguishable particles that obey non-abelian statistics.

Since the mid-1990s, Preskill research has focused on quantum computation and quantum information theory. With Peter Shor, he invented a powerful method, derived from entanglement theory, for proving the security of quantum protocols. With Daniel Gottesman and others, he developed the theory of fault-tolerant quantum computing and proved the quantum accuracy threshold theorem, which establishes that a noisy quantum computer can operate reliably if the noise is not too strong. With Alexei Kitaev and others, he showed that quantum information can be reliably stored and processed using methods based on topological principles, and that the quantum entanglement in topologically ordered quantum many-body systems has robust universal properties. With Gottesman and Kitaev, he introduced GKP codes, in which a finite-dimensional Hilbert space is robustly encoded in the infinite-dimension Hilbert space of a collection of harmonic oscillators. With Patrick Hayden, he applied quantum information methods to gravitational physics, showing that information can be revealed by an evaporating black hole surprisingly quickly. With Fernando Pastawski, Beni Yoshida, and Daniel Harlow, he constructed quantum error-correcting codes that capture essential features of quantum spacetime. With Robert Huang and Richard Kueng, he introduced the classical shadow formalism for efficiently predicting properties of many-particle quantum systems using randomized measurements.

Preskill’s celebrated lecture notes from his Caltech course on Quantum Computation, available online since 1997, have exerted a profound influence on the development of the subject. In 2000, Preskill founded Caltech’s Institute for Quantum Information, which since then has been one of the world’s leading centers for theoretical research on quantum information and quantum computing. In 2011, the IQI became part of the Institute for Quantum Information and Matter, an NSF Physics Frontiers Center.

Preskill is a member of the National Academy of Sciences, a fellow of the American Physical Society, and a two-time recipient of the Associated Students of Caltech Teaching Award. He received the 2024 John Stewart Bell Prize for Research on Fundamental Issues in Quantum Mechanics and the 2025 Academic Pioneer in Quantum Award from the Quantum World Congress. Among other honors, he has been the Lorentz Chair at the University of Leiden, the Rouse Ball Lecturer at the University of Cambridge, the Loeb Lecturer at Harvard University, the Aisenstadt Chair at the Centre de Recherches Mathématiques, the Arnold Sommerfeld Lecturer at the University of Munich, the American Mathematical Society Josiah Willard Gibbs Lecturer, the Oppenheimer Lecturer at UC Berkeley, the Bethe Lecturer at Cornell University, the Dirac Lecturer at the University of Cambridge, the Robert Hofstadter Lecturer at Stanford University, and the Wolfgang Pauli Lecturer at ETH Zurich. Preskill has mentored more than 60 Ph.D. students and more than 60 postdoctoral scholars at Caltech, many of whom are now leaders in their research areas.

[see short biography]