Greg Bryan

Greg Bryan is a theoretical and computational astrophysicist. His research focuses on understanding how cosmic structure forms and evolves—from the first stars in the universe, to the formation of galaxies like our own, to the hot gas in massive galaxy clusters. Much of this work uses large numerical simulations that follow dark matter, gas, stars, and black holes across cosmic time, with particular attention to the circumgalactic and intergalactic medium that fuels and regulates galaxy growth.

Professor Bryan directs the Simons Collaboration on Learning the Universe, which combines cosmological simulations with machine learning and Bayesian forward modeling to infer the initial conditions and physical laws of the universe from observations. Additionally, Professor Bryan is one of the original developers of Enzo, an open-source adaptive mesh refinement (AMR) code for astrophysics and cosmology, and contribute to its successor Enzo-E and the Grackle chemistry and cooling library.

Professor Bryan received his B.Sc. in physics from the University of Calgary (Canada) and his Ph.D. from the University of Illinois. He received a Hubble Fellowship, Lyman Spitzer Fellowship, and an NSF Career Grant. He also received the Leverhulme Trust Prize for “outstanding young researchers.” He was a faculty member in the Physics department at Oxford for three years before coming to Columbia University. He is the Director of the Simons Collaboration on Learning the Universe.