An "Ultrasonic Image" of the Embryonic Universe: CMB Polarization Tests   of the Inflationary Paradigm
  This chapter describes how the Cosmic Gravitational Wave Background induces a specific type of CMB polarization and describes the first experiment dedicated to testing this most-promising signature of inflation. This experiment, the Background Imaging of Cosmic Extragalactic Polarization (BICEP) project, has recently embarked on its third observing season. We show preliminary data from the BICEP's first season obtained with a novel polarization modulation mechanism called the "Faraday Rotation Modulator". Our discussion ends with a description of exciting new technology with the potential to probe inflation down to the GUT-scale. 
Brian G. Keating