Collaborative Research: Imaging the Beginning of Time from the South Pole: Observations with the Full SPUD Array

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There is mounting evidence that the entire observable Universe was spawned in a dramatic superluminal "Inflation" of a subnuclear volume. This violent acceleration of matter would have produced a Cosmic Gravitational-wave Background (CGB), the amplitude of which measures the energy scale at which Inflation occurred. The CGB imprints a faint signature in the polarization of the Cosmic Microwave Background (CMB) with the amplitude parameterized by the ratio of tensor-to-scalar modes, r = T/S. Many theoretically favored models of Inflation produce this ratio between 0.01 and 0.1, corresponding to average amplitude from 30 to 100 nanoKelvins for the resulting CMB B-mode polarization patterns where they peak on scales of degrees. With this award, researchers from three U.S. institutions will focus on exploring and ultimately detecting the CGB polarization signature, which is arguably the most important goal in cosmology today. In 2005, the Community Task Force on CMB Research identified a target sensitivity of that ratio equaling to 0.02 as an immediate goal to detect the Inflationary gravitational waves imprint in the CMB polarization that pertain to the standard cosmological model. The newly installed 'Small Polarimeter Upgrades for DASI' (SPUD) reconfigured a five- receivers telescope to the "South Pole Inflationary Cosmology Experiment" (SPICE) that will: (a) Complete the CGB search in CMB B-mode polarization at 150 GHz, reaching depths which based on current sensitivity performance, that will detect the Inflationary CGB for r 0.02; (b) Prove that this signal is cosmic in origin while separately measuring the Galactic foreground contamination at its minimum; (c) Detect gravitational lensing of CMB polarization on scales of ~1 degree, probing the CGB to the lensing confusion limit for degree-scale observations (r 0.01) if the energy scale of Inflation is low; and (d) Surpass the instrumental sensitivity goals set forth for 2013 by the 2005 CMB Task Force recommendations. Detection of the CGB waves would be to Inflation what the discovery of the CMB radiation was to the Big Bang theory. Indeed, its impact may be even broader as nuclear physics had matured enough prior to the establishment of the "hot" Big Bang model, while Inflation directly bears on the current frontiers of fundamental physics: the union of general relativity and quantum mechanics, string theory, and the highest accessible energies. Cosmology and research in Antarctica both capture the public imagination, making this combination a remarkably effective vehicle for stimulating interest in science and train students.