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arXiv · 0904.4295

Computation of inflationary cosmological perturbations in chaotic inflationary scenarios using the phase-integral method

Clara Rojas·Victor M. Villalba
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Abstract

The phase-integral approximation devised by Fröman and Fröman, is used for computing cosmological perturbations in the quadratic chaotic inflationary model. The phase-integral formulas for the scalar and tensor power spectra are explicitly obtained up to fifth order of the phase-integral approximation. We show that, the phase integral gives a very good approximation for the shape of the power spectra associated with scalar and tensor perturbations as well as the spectral indices. We find that the accuracy of the phase-integral approximation compares favorably with the numerical results and those obtained using the slow-roll and uniform approximation methods.

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Clara Rojas, Victor M. Villalba. 2009-04-28. Computation of inflationary cosmological perturbations in chaotic inflationary scenarios using the phase-integral method. https://doi.org/10.1103/physrevd.79.103502

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