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arXiv · 1508.06727

Approach to exact solutions of cosmological perturbations: Tachyon field inflation

Ramon Herrera·Roberto G. Perez
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Abstract

An inflationary universe scenario in the context of tachyon field is studied. This study is done from an ansantz for the effective potential of cosmological perturbations $U(\eta)$. We describe in great detail the analytical solutions of the scalar and tensor perturbations for two different ansantz in the effective potential of cosmological perturbations; the Easther's model and an effective potential similar to power law inflation. Also we find from the background equations that the effective tachyonic potential $V(\varphi)$, in both models satisfy the properties of a tachyonic potential. We consider the recent data from the Planck data to constrain the parameters in our effective potential of cosmological perturbations.

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Ramon Herrera, Roberto G. Perez. 2015-08-27. Approach to exact solutions of cosmological perturbations: Tachyon field inflation. https://doi.org/10.1103/physrevd.93.063516

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