Motivated by the idea that inflation occurs at the GUT symmetry breakingscale, in this paper we construct a new class of large field inflatonpotentials where the inflaton starts with a power law potential; after initialperiod of relative fast roll that lasts until after a few e-folds inside thehorizon, it transits to the attractor of the slow roll part of the potentialwith a lower power. Due to the initial fast roll stages of inflation, we find asuppression in scalar primordial power at large scales and at the same time thechoice of the potential can provide us a tensor primordial spectrum with highamplitude. This suppression in scalar power with a large tensor-to-scalar ratiohelps us to reconcile the Planck and BICEP2 data in a single framework. We findthat a transition from a cubic to quadratic form of inflaton potentialgenerates an appropriate suppression in power of scalar primordial spectrumthat provides significant improvement in fit compared to power law model whencompared with Planck and BICEP2 data together. We calculate the extent ofnon-Gaussianity, specifically, the bispectrum for the best fit potential andshow that it is consistent with Planck bispectrum constraints.
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