High-energy physics and cosmological perturbations: observing new
  physics at large scales
  Correlators of primordial perturbations could provide us with the signatures
of physics at earlier times/higher momentum scales than inflation. The
key-mechanisms are the interference and cumulation in time related to the
interplay of negative- and positive-frequency components of fields and energy
density generated by the high-momentum scale physics. Here, we discuss which
signatures are universal for such scenarios, and which ones instead would
distinguish the specific cases (for example modified initial states for
inflationary perturbations or modified dispersion relations). We also discuss
the scale dependence of the correlators in presence of these signatures,
especially for some scenarios, and how this could be interesting for
observations.
