2009/04/28 by Clara Rojas, Victor M. Villalba, Vı́ctor M. Villalba · 1 citation
Earth and Planetary Sciences · Physics and Astronomy · #Cosmology and Gravitation Theories #Galaxies: Formation, Evolution, Phenomena #Geophysics and Gravity Measurements #gr-qc
paper · pdf · doi:10.1103/physrevd.79.103502
published as Phys.Rev.D79:103502,2009 · 21 pages, RevTex, to appear in Phys. Rev D
arxiv created 2009/04/28 · openalex publication_date 2009/05/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
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.