Evolution of the spectral index after inflation
Abstract
In this article we investigate the time evolution of the adiabatic (curvature) and isocurvature (entropy) spectral indices after inflation era for all cosmological scales with two different initial conditions. For this purpose, we first extract an explicit equation for the time evolution of the comoving curvature perturbation (which may be known as the generalized MukhanovSasaki equation). It would be cleared that the evolution of adiabatic spectral index severely depends on the initial conditions moreover, as expected it is constant only for the superHubble scales and adiabatic initial conditions. Additionally, the adiabatic spectral index after recombination approaches a constant value for the isocurvature perturbations. Finally, we reinvestigate the SachsWolfe effect and show that the fudge factor 1/3 in the adiabatic ordinary SachsWolfe formula must be replaced by 0.4.
 Authors:
 Department of Physics, School of Sciences, Tarbiat Modares University, P.O.Box 141554838, Tehran (Iran, Islamic Republic of)
 Publication Date:
 OSTI Identifier:
 22375867
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2014; Journal Issue: 09; Other Information: Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; COSMOLOGICAL INFLATION; DATA; ENTROPY; EQUATIONS; EVOLUTION; PERTURBATION THEORY
Citation Formats
Asgari, A.A., and Abbassi, A.H., Email: aliakbar.asgari@modares.ac.ir, Email: ahabbasi@modares.ac.ir. Evolution of the spectral index after inflation. United States: N. p., 2014.
Web. doi:10.1088/14757516/2014/09/042.
Asgari, A.A., & Abbassi, A.H., Email: aliakbar.asgari@modares.ac.ir, Email: ahabbasi@modares.ac.ir. Evolution of the spectral index after inflation. United States. doi:10.1088/14757516/2014/09/042.
Asgari, A.A., and Abbassi, A.H., Email: aliakbar.asgari@modares.ac.ir, Email: ahabbasi@modares.ac.ir. Mon .
"Evolution of the spectral index after inflation". United States.
doi:10.1088/14757516/2014/09/042.
@article{osti_22375867,
title = {Evolution of the spectral index after inflation},
author = {Asgari, A.A. and Abbassi, A.H., Email: aliakbar.asgari@modares.ac.ir, Email: ahabbasi@modares.ac.ir},
abstractNote = {In this article we investigate the time evolution of the adiabatic (curvature) and isocurvature (entropy) spectral indices after inflation era for all cosmological scales with two different initial conditions. For this purpose, we first extract an explicit equation for the time evolution of the comoving curvature perturbation (which may be known as the generalized MukhanovSasaki equation). It would be cleared that the evolution of adiabatic spectral index severely depends on the initial conditions moreover, as expected it is constant only for the superHubble scales and adiabatic initial conditions. Additionally, the adiabatic spectral index after recombination approaches a constant value for the isocurvature perturbations. Finally, we reinvestigate the SachsWolfe effect and show that the fudge factor 1/3 in the adiabatic ordinary SachsWolfe formula must be replaced by 0.4.},
doi = {10.1088/14757516/2014/09/042},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 09,
volume = 2014,
place = {United States},
year = {Mon Sep 01 00:00:00 EDT 2014},
month = {Mon Sep 01 00:00:00 EDT 2014}
}

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