Breaking of Spatial Diffeomorphism Invariance, Inflation and the
  Spectrum of Cosmological Perturbations
  Standard inflationary models yield a characteristic signature of a primordial
power spectrum with a red tensor and scalar tilt. Nevertheless, Cannone et al
recently suggested that, by breaking the assumption of spatial diffeomorphism
invariance in the context of the effective field theory of inflation, a blue
tensor spectrum can be achieved without violating the Null Energy Condition. In
this context, we explore in which cases a blue tensor tilt can be obtained
along with a red tilt in the scalar spectrum. Ultimately, we analyze under
which conditions this model can reproduce the specific consistency relation of
String Gas Cosmology.
