Speaker: Brian Keating, UCSD Department of Physics
Abstract: The Background Imager of Cosmic Extragalactic Polarization (BICEP) experiment is the first cosmic microwave background (CMB) polarimeter designed to measure the "B-mode" polarization of the CMB, hypothesized to originate during the Inflationary epoch. Beginning in 2006 BICEP observed 3% of the sky from our observatory at the Amundsen-Scott South Pole Research Station in Antarctica. In this colloquium I will present our initial results and discuss the unique design features of BICEP which led to the first meaningful limits on the energy scale of Inflation to come from CMB polarization. Soon after BICEP's initial results were released, a publication (Xia, Li & Zhang, 2009), claimed a first-detection of parity-violating "cosmic birefringence" effects using publicly available BICEP data. I will discuss the challenges of polarimetry at the few parts per billion level and explain why systematic effects are particularly pernicious for probes of cosmic parity violation. I will conclude by discussing how BICEP and its successor, BICEP2, currently in its second observing season at the South Pole will constrain Inflationary cosmology and future measurements of cosmic birefringence.