Signatures of Supersymmetry from the Early Universe
  Supersymmetry plays a fundamental role in the radiative stability of many
inflationary models. Spontaneous breaking of the symmetry inevitably leads to
fields with masses of order the Hubble scale during inflation. When these
fields couple to the inflaton they produce a unique signature in the squeezed
limit of the three-point function of primordial curvature perturbations. In
this paper, we make this connection between naturalness, supersymmetry,
Hubble-mass degrees of freedom and the squeezed limit precise. To study the
physics in a model-insensitive way, we develop a supersymmetric effective
theory of inflation. We use the effective theory to classify all possible
interactions between the inflaton and the additional fields, and determine
which ones naturally allow large non-Gaussianities when protected by
supersymmetry. Finally, we discuss the tantalizing prospect of using
cosmological observations as a probe of supersymmetry.
