Joint Astrophysics Colloquium

Resolving New Aspects of the Cosmic Microwave Background

Joe Fowler

Princeton University

The numerous observations of anisotropies in the cosmic microwave background (CMB) over the last two decades have provided a new view of the universe and a standard model of cosmology. The data support the basic picture of inflation and the hot Big Bang, and they allow us to estimate multiple cosmological parameters with nearly percent-level precision. While the all-sky maps from orbital missions are enormously valuable, there remains much to learn from terrestrial observations of the small-scale CMB anisotropies. They can tell us about the emergence of structure in the large-scale distribution of matter and the properties of the dark energy. Their power spectrum is sensitive to parameters of the quantum field governing the epoch of inflation. With the new Atacama Cosmology Telescope, we are starting to map the CMB at arcminute resolution to address these questions. These small-scale temperature anisotropies, along with the polarization of the CMB at a wide range of angular scales, offer fertile ground for many fruitful observations in the decade to come.