  A corpuscular quantum description of inflation shows that there is no
fundamental problem with trans-Planckian excursions of the inflaton field up to
about 100 Planck masses, with the upper bound coming from the corpuscular
quantum effects. In this description the r-parameter measures the ratio of
occupation numbers of gravitons versus inflatons, which, according to BICEP2,
was roughly a half at the time of 60 e-foldings prior to the end of inflation.
We stress that in non-Wilsonian UV self-completion of gravity any
trans-Planckian mode coupled to inflaton is a black hole. Unlike the Wilsonian
case, their integration-out gives an exponentially-suppressed effect and is
unable to prevent trans-Planckian excursions of the inflaton field.
