Abstract
I am showing in this paper that it is possible to attain very high, including observable, values for the leve! of non-gaussianity f N L in a particular quadratic two-field slow-roll model of inflation with canonical kinetic terms. This is done by taking care of loop corrections both in the spectrum Pζ and the bispectrum Bζ; of the primordial curvature perturbation ζ. Sizable values for f N L arise even if ζ is generated during inflation. Five issues are considered when constraining the available parameter space: 1. we must ensure that we are in a perturbative regime so that the ζ series expansion, and its truncation, are valid. 2. we must apply the correct condition for the (possible) loop dominance in Bζ and/or Pζ. 3 we must satisfy the spectrum normalisation condition. 4. we must satisfy the spectral tilt constraint. 5. we must have enough inflation to sol ve the horizon problem.
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