Probing New Physics with the Cosmic Microwave Background (speaker: Abigail Vieregg, University of Chicago)
Measurements of the Cosmic Microwave Background (CMB) have been extremely important for our understanding of the origin, contents, and evolution of the universe. Increasingly precise maps of the CMB are a unique and powerful tool for understanding new physics, including inflation, the superluminal expansion of the universe during the first moments after the Big Bang. I will discuss the current status of CMB measurements, focusing on constraints on inflation with the BICEP series of experiments at the South Pole (BICEP2, The Keck Array, and BICEP3). I will then discuss the rapidly moving plans for a next-generation ground-based program called CMB-S4. The sensitivity leap of CMB-S4 is needed to pass critical thresholds in our understanding of inflation, neutrino mass, and in searches for additional light relativistic species.