Probing Planckian physics: Resonant production of particles during inflation and features in the primordial power spectrum - art. no. 043508

The phenomenon of the resonant production of particles after inflation has received much attention in the past few years. In a new application of the resonant production of particles, we consider the effect of a resonance hir ing inflation. We show that if the inflaton is coupled to a massive particl e, resonant production of the particle during inflation modifies the evolut ion of the inflaton, and may leave an imprint in the form of sharp features in the primordial power spectrum. Precision measurements of microwave back ground anisotropies and large-scale structure surveys could be sensitive to the features, and probe the spectrum of particles as massive as the Planck scale.