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arXiv · 1311.5327

Consistency of the tachyon warm inflationary universe models

Xiao-Min Zhang·Jian-Yang Zhu
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Abstract

This study concerns the consistency of the tachyon warm inflationary models. A linear stability analysis is performed to find the slow-roll conditions, characterized by the potential slow-roll (PSR) parameters, for the existence of a tachyon warm inflationary attractor in the system. The PSR parameters in the tachyon warm inflationary models are redefined. Two cases, an exponential potential and an inverse power-law potential, are studied, when the dissipative coefficient $Γ=Γ_0$ and $Γ=Γ(ϕ)$, respectively. A crucial condition is obtained for a tachyon warm inflationary model characterized by the Hubble slow-roll (HSR) parameter $ε_{_H}$, and the condition is extendable to some other inflationary models as well. A proper number of e-folds is obtained in both cases of the tachyon warm inflation, in contrast to existing works. It is also found that a constant dissipative coefficient $(Γ=Γ_0)$ is usually not a suitable assumption for a warm inflationary model.

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Xiao-Min Zhang, Jian-Yang Zhu. 2014-01-31. Consistency of the tachyon warm inflationary universe models. https://doi.org/10.1088/1475-7516%2F2014%2F02%2F005

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