Douglas Scott (University of British Columbia)

Douglas Scott Colloquium: The Standard Cosmological Model

Kensington

Abstract

All empirical data relating to our Universe are currently well fit by a basic model that contains only a few key ingredients: the background is described by homogeneous and isotropic solutions within General Relativity, in which there is domination by vacuum energy and cold dark matter in a roughly flat expanding geometry; the density fluctuations appear to be nearly scale-invariant, adiabatic and Gaussian (close to the simplest thing we could imagine); and all of today’s structure grew through gravitational instability. Within this picture the Universe is described by just a handful of numbers, which are now known to quite high precision. So what is left to do in cosmology? How many digits of precision do we need? Where did these values come from? Are there more numbers that we haven’t thought of yet? Is this model anything like the Standard Model of Particle Physics? Are there signs that we need “physics beyond the standard model"? Did someone say "anomalies" and "tensions”?