Inflation and classical scale invariance
  BICEP2 measurement of primordial tensor modes in CMB suggests that
cosmological inflation is due to a slowly rolling inflaton taking
trans-Planckian values and provides further experimental evidence for the
absence of large $M_{\rm P}$ induced operators. We show that classical scale
invariance solves the problem and allows for a remarkably simple scale-free
inflaton model without any gauge group. Due to trans-Planckian inflaton values
and VEVs, a dynamically induced Coleman-Weinberg-type inflaton potential of the
model can predict tensor-to-scalar ratio $r$ in a large range. Precise
determination of $r$ in future experiments will allow to test the proposed
field-theoretic framework.
