Small-scale Tests of Inflation
  We investigate small-scale signatures of the inflationary particle content.
We consider the case of a light spin-2 particle sourcing primordial
gravitational waves by employing an effective field theory description. Upon
allowing time-dependent sound speeds for the helicity modes, this setup
delivers a blue tensor spectrum detectable, for example, by upcoming laser
interferometers. Our focus is on the tensor non-Gaussianities that ensue from
this field configuration. After characterising the bispectrum amplitude and
shape-function at CMB scales, we move on to smaller scales where anisotropies
induced in the tensor power spectrum by long-short modes coupling become the
key handle on (squeezed) primordial non-Gaussianities. We identify the
parameter space generating percent level anisotropies at scales soon to be
probed by SKA and LISA.
