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Scalar perturbation spectra from warm inflation

Lisa M. H. Hall·Ian G. Moss·Arjun Berera
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Abstract

We present a numerical integration of the cosmological scalar perturbation equations in warm inflation. The initial conditions are provided by a discussion of the thermal fluctuations of an inflaton field and thermal radiation using a combination of thermal field theory and thermodynamics. The perturbation equations include the effects of a damping coefficient $Γ$ and a thermodynamic potential $V$. We give an analytic expression for the spectral index of scalar fluctuations in terms of a new slow-roll parameter constructed from $Γ$. A series of toy models, inspired by spontaneous symmetry breaking and a known form of the damping coefficient, lead to a spectrum with $n_s>1$ on large scales and $n_s<1$ on small scales.

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Lisa M. H. Hall, Ian G. Moss, Arjun Berera. 2003-11-22. Scalar perturbation spectra from warm inflation. https://doi.org/10.1103/physrevd.69.083525

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