Inflation: Observational Status and Future Prospects


Prof. Richard Easther, The University of Auckland

Inflation—a period of accelerated expansion in the very early universe—sets the initial conditions for cosmology, ensuring that the visible universe is uniform on large scales while providing the seeds for structure formation and the hot and cold spots in the microwave background. Inflation received a huge boost in March this year when BICEP2 reported evidence for a cosmic gravitational wave background. ¬†Not only is a detectable gravitational wave background predicted by a large class of inflationary models, almost all competing mechanisms for fixing cosmological initial conditions predict that the gravitational wave background is unobservably small. ¬†Finally, BICEP2 (and its likely successors) provide an unprecedented opportunity for probing the inflationary mechanism itself, with fascinating implications for both cosmology and high energy physics.
In this colloquium, I will give a broad overview of the status of inflationary cosmology in the light of recent data and discuss my own work, including novel approaches to constraining specific inflationary scenarios and the surprisingly simple predictions made by sophisticated models of inflation driven by multiple, interacting degrees of freedom.