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Title: Computation of inflationary cosmological perturbations in the power-law inflationary model using the phase-integral method

Abstract

The phase-integral approximation devised by Froeman and Froeman, is used for computing cosmological perturbations in the power-law inflationary model. The phase-integral formulas for the scalar and tensor power spectra are explicitly obtained up to ninth-order of the phase-integral approximation. We show that, the phase-integral approximation exactly reproduces the shape of the power spectra for scalar and tensor perturbations as well as the spectral indices. We compare the accuracy of the phase-integral approximation with the results for the power spectrum obtained with the slow-roll and uniform-approximation methods.

Authors:
;  [1]
  1. Centro de Fisica IVIC Apdo 21827, Caracas 1020A (Venezuela)
Publication Date:
OSTI Identifier:
21020142
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevD.75.063518; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ACCURACY; APPROXIMATIONS; COMPARATIVE EVALUATIONS; COSMOLOGY; ENERGY SPECTRA; INFLATIONARY UNIVERSE; SCALARS; TENSORS

Citation Formats

Rojas, Clara, and Villalba, Victor M. Computation of inflationary cosmological perturbations in the power-law inflationary model using the phase-integral method. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.063518.
Rojas, Clara, & Villalba, Victor M. Computation of inflationary cosmological perturbations in the power-law inflationary model using the phase-integral method. United States. doi:10.1103/PHYSREVD.75.063518.
Rojas, Clara, and Villalba, Victor M. Thu . "Computation of inflationary cosmological perturbations in the power-law inflationary model using the phase-integral method". United States. doi:10.1103/PHYSREVD.75.063518.
@article{osti_21020142,
title = {Computation of inflationary cosmological perturbations in the power-law inflationary model using the phase-integral method},
author = {Rojas, Clara and Villalba, Victor M.},
abstractNote = {The phase-integral approximation devised by Froeman and Froeman, is used for computing cosmological perturbations in the power-law inflationary model. The phase-integral formulas for the scalar and tensor power spectra are explicitly obtained up to ninth-order of the phase-integral approximation. We show that, the phase-integral approximation exactly reproduces the shape of the power spectra for scalar and tensor perturbations as well as the spectral indices. We compare the accuracy of the phase-integral approximation with the results for the power spectrum obtained with the slow-roll and uniform-approximation methods.},
doi = {10.1103/PHYSREVD.75.063518},
journal = {Physical Review. D, Particles Fields},
number = 6,
volume = 75,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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