Evolution of large scale curvature fluctuations during the perturbative decay of the inflaton

  title={Evolution of large scale curvature fluctuations during the perturbative decay of the inflaton},
  author={F. Marco and F. Finelli and A. Gruppuso},
  journal={Physical Review D},
We study the evolution of cosmological fluctuations during and after inflation driven by a scalar field coupled to a perfect fluid through a friction term. During the slow-roll regime for the scalar field, the perfect fluid is also frozen and isocurvature perturbations are generated. After the end of inflation, during the decay of the inflaton, we find that a change in the observationally relevant large scale curvature fluctuations is possible. 

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