Title: "Imaging the Beginning of Time from the Bottom of the World: the Search for Inflation with BICEP2 and the Keck Array at the South Pole"
Abstract: Inflation, the superluminal expansion of the universe during the first moments after the Big Bang, predicts a Cosmic Gravitational-Wave Background, which in turn imprints a faint but unique signature of “B-mode” polarization of the Cosmic Microwave Background (CMB). The Keck Array, currently beginning fourth observing season at the South Pole, is a suite of five microwave polarimeters that use antenna-coupled Transition Edge Sensor arrays to observe the CMB at degree angular scales and is specifically designed to search for this signature of Inflation. The Keck Array builds upon the success of its predecessor experiments BICEP1 (observed 2006-2008) and BICEP2 (observed 2010-2012), employing the same field-proven detection strategy but with vastly improved sensitivity. BICEP2 and the Keck Array are well-positioned to be the first experiments to actually detect this signature of Inflation, testing models of Inflation at the GUT scale. In the next decade, precision measurements of CMB polarization promise to probe a wide variety of fundamental physics, including the energy scale of Inflation, dark energy in the early universe, and the sum of the neutrino masses.