Biermann lectures 2023: Do we have a standard model of cosmology?
By Prof. George Efstathiou, University of Cambridge
About 50 years ago, Simon White, Carlos Frenk and Marc Davis teamed up with George Efstathiou to find an explanation for the large-scale structures observed in the galaxy distribution – establishing “Cold Dark Matter” as the standard model of cosmology. Even though inflation and dark energy had to be incorporated in later years, the basic framework still stands. In this year’s Biermann lecture, George Efstathiou will explain how ΛCDM cosmology became the standard model for cosmology, its limitations, and how it might evolve in the future.
In the 1970s, large surveys of the three-dimensional galaxy distribution had revealed filaments and voids, which was at odds with the uniform matter distribution at the beginning of the universe as seen in the Cosmic Microwave Background. George Efstathiou worked on early computational models of cosmological structure formation, and together with Davis, Frenk and White, he carried out the first cosmological simulations of the cold dark matter model, which to the team’s surprise were a close match to the observations. In the late 1980s, the DEFW collaboration produced five papers that established “CDM” as the standard cosmological model.
In 1990, Efstathiou led the study that reported an early indication of a cosmological constant using galaxy survey data from the APM survey. He thus inferred the existence of dark energy years before the discovery of the accelerated expansion of the universe through supernova data. Therefore, dark energy was added to establish the current ΛCDM, for which Efstathiou received the 2011 Gruber Cosmology Prize jointly awarded with Marc Davis, Carlos Frenk and Simon White. He has been involved in many other galaxy surveys such as the “2-degree-field galaxy redshift survey” (2dFGRS), which first detected ‘baryon acoustic oscillations’.
In addition to his research on large-scale cosmic structure formation, George Efstathiou also made fundamental contributions to investigations of the anisotropies in the cosmic microwave background. With J. Richard Bond, Efstathiou performed the most comprehensive calculation of statistical properties of the CMB, most notably including polarization and the impact of CDM. As a member of the Science Team for the European Space Agency Planck satellite, he made significant contributions to the most detailed analysis to date of the CMB.
George Efstathiou received his B.A. in Physics from Keble College, Oxford University in 1976, and his Ph.D. in Astronomy from Durham University in 1979. Postdoc positions at the Department of Astronomy, University of California, Berkeley, and the Institute for Astronomy at Cambridge led to him becoming Assistant Director of Research. From 1988 to 1994, Efstathiou was the Head of Astrophysics at Oxford University, and returned to Cambridge in 1997, where he has served as Director of the Institute of Astronomy since 2004. He was appointed as the first Director of the Kavli Institute for Cosmology at Cambridge from 2008 – 2013.
Professor Efstathiou has received several prizes for his research including the 1990 Maxwell Medal and Prize of the Institute of Physics, the 2005 American Institute of Physics Heineman Prize for Astronomy (shared with his long-term collaborator Simon White), as mentioned above in 2011 the Gruber Cosmology Prize, and in 2022 the Gold Medal in Astronomy from the Royal Astronomical Society.
Overall title: Do we have a standard model of cosmology?
All lectures take place in the MPA Large Seminar Room E.0.11 and will be preceded by tea, coffee and cookies 15 minutes before the lecture starts.
Wednesday, July 5, 15:30
The LCDM cosmology
Wednesday, July 12, 15:30
Tensions in cosmology?
Wednesday July 19, 15:30
Cosmology in crisis