A Quantum Window Onto Early Inflation
  Inflation in the early Universe is one of the most promising probes of
gravity in the high-energy regime. However, observable scales give access to a
limited window in the inflationary dynamics. In this essay, we argue that
quantum corrections to the classical dynamics of cosmological fields allow us
to probe much earlier epochs of the inflationary phase and extend this window
by many orders of magnitude. We point out that both the statistics of
cosmological fluctuations at observable scales, and the field displacements
acquired by spectator fields that play an important role in many
post-inflationary processes, are sensitive to a much longer phase of the
inflationary epoch.
