WATCH: CCA Seminar with Colin Hill

Observations of the cosmic microwave background (CMB) radiation have driven the current era of precision cosmology. Nevertheless, substantial information remains to be extracted from the primary CMB polarization anisotropies — including the signature of primordial gravitational waves — as well as the “secondary anisotropies” generated by effects between our vantage point and the surface of last scattering. The latter signals, including gravitational lensing and the thermal and kinematic Sunyaev-Zel’dovich (SZ) effects, also contain valuable astrophysical information about the distribution of baryons and dark matter at late times. I will present ongoing work to extract these signals in data from the Atacama Cosmology Telescope, as well as next-generation forecasts for the Simons Observatory (SO), which will begin observations in less than two years. Throughout, I will highlight novel foreground mitigation methods that I have developed, which are enabled by CMB observations at multiple frequencies. Applied to upcoming SO measurements of the SZ effects, CMB lensing, and primordial non-Gaussianity, these methods will yield transformative constraints on inflation, neutrino properties, and feedback mechanisms in galaxy formation and evolution. I will conclude with a look ahead to novel discovery space in measurements of the CMB energy spectrum.