Deriving superhorizon curvature perturbations from the dynamics of preheating
Abstract
We present a framework for calculating superhorizon curvature perturbation from the dynamics of preheating, which gives a reasonable match to the lattice results. Hubble patches with different initial background field values evolve differently. From the bifurcation of their evolution trajectories we find curvature perturbation using Lyapunov theorem and δ N formulation. In this way we have established a connection between the finer dynamics of preheating and the curvature perturbation produced in this era. From the calculated analytical form of the curvature perturbation we have derived the effective superhorizon curvature perturbation smoothed out on large scales of CMB. The order of the amount of local form nongaussianity generated in this process has been calculated and problems regarding the precise determination of it have been pointed out.
 Authors:
 Theory Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata64 (India)
 Astroparticle Physics and Cosmology Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata64 (India)
 Publication Date:
 OSTI Identifier:
 22525861
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2015; Journal Issue: 04; Other Information: Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BIFURCATION; DISTURBANCES; HEATING; LYAPUNOV METHOD; RELICT RADIATION; TRAJECTORIES; UNIVERSE
Citation Formats
Mazumdar, Arindam, and Modak, Kamakshya Prasad, Email: arindam.mazumdar@saha.ac.in, Email: kamakshya.modak@saha.ac.in. Deriving superhorizon curvature perturbations from the dynamics of preheating. United States: N. p., 2015.
Web. doi:10.1088/14757516/2015/04/053.
Mazumdar, Arindam, & Modak, Kamakshya Prasad, Email: arindam.mazumdar@saha.ac.in, Email: kamakshya.modak@saha.ac.in. Deriving superhorizon curvature perturbations from the dynamics of preheating. United States. doi:10.1088/14757516/2015/04/053.
Mazumdar, Arindam, and Modak, Kamakshya Prasad, Email: arindam.mazumdar@saha.ac.in, Email: kamakshya.modak@saha.ac.in. 2015.
"Deriving superhorizon curvature perturbations from the dynamics of preheating". United States.
doi:10.1088/14757516/2015/04/053.
@article{osti_22525861,
title = {Deriving superhorizon curvature perturbations from the dynamics of preheating},
author = {Mazumdar, Arindam and Modak, Kamakshya Prasad, Email: arindam.mazumdar@saha.ac.in, Email: kamakshya.modak@saha.ac.in},
abstractNote = {We present a framework for calculating superhorizon curvature perturbation from the dynamics of preheating, which gives a reasonable match to the lattice results. Hubble patches with different initial background field values evolve differently. From the bifurcation of their evolution trajectories we find curvature perturbation using Lyapunov theorem and δ N formulation. In this way we have established a connection between the finer dynamics of preheating and the curvature perturbation produced in this era. From the calculated analytical form of the curvature perturbation we have derived the effective superhorizon curvature perturbation smoothed out on large scales of CMB. The order of the amount of local form nongaussianity generated in this process has been calculated and problems regarding the precise determination of it have been pointed out.},
doi = {10.1088/14757516/2015/04/053},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 04,
volume = 2015,
place = {United States},
year = 2015,
month = 4
}

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