Will Kinney (SUNY Buffalo, United States)
Recent data from the Cosmic Microwave Background and Large-Scale structure confirm the basic predictions of inflation in the early universe: a Gaussian, adiabatic spectrum of density perturbations with correlations on super-Hubble length scales. Furthermore, the density perturbations are known to be nearly (but not exactly) scale-invariant over a factor of at least a thousand in wavelength. I ask the question: what is the most general conclusion that can be drawn from these observational facts about the universe, consistent with standard General Relativity? Are superhorizon scalar modes a "smoking gun" for inflation, or are other scenarios possible? What would an observation of primordial tensor modes add?