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arXiv · 1103.0912

Second Order Perturbations During Inflation Beyond Slow-roll

Ian Huston·Karim A. Malik
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Abstract

We numerically calculate the evolution of second order cosmological perturbations for an inflationary scalar field without resorting to the slow-roll approximation or assuming large scales. In contrast to previous approaches we therefore use the full non-slow-roll source term for the second order Klein-Gordon equation which is valid on all scales. The numerical results are consistent with the ones obtained previously where slow-roll is a good approximation. We investigate the effect of localised features in the scalar field potential which break slow-roll for some portion of the evolution. The numerical package solving the second order Klein-Gordon equation has been released under an open source license and is available for download.

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BibTeXRIS

Ian Huston, Karim A. Malik. 2011-11-14. Second Order Perturbations During Inflation Beyond Slow-roll. https://doi.org/10.1088/1475-7516%2F2011%2F10%2F029

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