Observational constraints on models of inflation from the density perturbation and gravitino production

David H. Lyth

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arXiv · hep-ph/0012065

Observational constraints on models of inflation from the density perturbation and gravitino production

David H. Lyth

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Abstract

Present data require a spectral index $n\gsim 0.95$ at something like 1-$σ$ level. If this lower bound survives it will constrain `new' and `modular' inflation models, while raising it to 1.00 would rule out all of these models plus many others. After inflation, gravitinos are created by the oscillating field until the `intermediate' epoch when the Hubble parameter falls below the gravitino mass, or reheating, whichever is earlier. In a wide range of parameter space, these gravitinos are more abundant than those from thermal collisions, leading to stronger cosmological constraints.

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David H. Lyth. 2000-12-06. Observational constraints on models of inflation from the density perturbation and gravitino production. https://arxiv.org/abs/hep-ph/0012065

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