Josh Frieman Josh Frieman

Josh Frieman is a senior staff member (Scientist III) in the Theoretical Astrophysics group at Fermilab and the Fermilab Center for Particle Astrophysics. He is also Professor of Astronomy and Astrophysics at the University of Chicago, where he is a member of the Kavli Institute for Cosmological Physics.
Frieman earned a B.Sc. degree from Stanford (1981) and a PhD in Physics from the University of Chicago (1985). After a postdoc in the SLAC Theory Group, he joined the scientific staff at Fermilab in 1988. He served as Head of the Theoretical Astrophysics Group from 1994 to 1999. He is an Honorary Fellow of the Royal Astronomical Society, and a Fellow of the American Physical Society and of the American Association for the Advancement of Science. He is Vice-President and former Trustee of the Aspen Center for Physics. He has served on the Executive Committee of the APS Divison of Astrophysics, on the Particle Physics Project Prioritization Panel (P5) of HEPAP, on the Astro 2010 Decadal Survey Committee, on the Astronomy and Astrophysics Advisory Committee (AAAC), and on the NRC Committee on Astronomy and Astrophysics.

Frieman's research centers on theoretical and observational cosmology, including studies of the nature of dark energy, the early Universe, gravitational lensing, the large-scale structure of the Universe, and supernovae as cosmological distance indicators. The author of over 275 publications, he led the Sloan Digital Sky Survey (SDSS-II) Supernova Survey, which discovered over 500 type Ia supernovae for cosmology studies, served as chair of the SDSS Collaboration Council, and as co-lead of the SDSS Large-scale Structure Working Group. He is a founder of and currently serves as Director of the Dark Energy Survey, a collaboration of over 300 scientists from 25 institutions on 3 continents, which built a 570-Megapixel camera to carry out a wide-field survey on the Blanco 4-meter telescope at Cerro Tololo Inter-American Observatory in Chile to probe the origin of cosmic acceleration. Frieman’s recent scientific papers can be found on the preprint ArXiv,

His webpage at U. Chicago contains some additional content on graduate and undergraduate courses taught, a sampling of conference talks, and other assorted miscellania, not in a currently well-organized fashion.

Contact information:
  • E-mail address: frieman at
  • Telephone: (630) 840-2226 (Fermilab), (773)702-7971 (U. Chicago)
  • Fax: (630) 840-8231
  • Mail Address: MS 209, Fermilab, P.O. Box 500, Batavia, IL 60510
  • Location: Fermilab: Wilson Hall, 6th Floor, west side. U. Chicago: Temporary Astronomy and Astrophysics Center, Room 24
  • Also reachable through my administrative assistant: Connie Lang, (630)840-8020, langcm60 at