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Title: Scale-invariant perturbations from chaotic inflation

Abstract

Vacuum fluctuations in the inflaton field driving chaotic inflation with a quadratic potential give a red spectrum of primordial density perturbations, n=0.97. However angular fluctuations in an O(N)-symmetric quadratic potential have a very nearly scale-invariant spectrum, n=0.9998. We investigate the possibility that these isocurvature field perturbations could give the dominant contribution to the primordial density perturbation after inflation.

Authors:
;  [1]
  1. Institute of Cosmology and Gravitation, University of Portsmouth, Portsmouth PO1 2EG (United Kingdom)
Publication Date:
OSTI Identifier:
20782613
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 73; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevD.73.063509; (c) 2006 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; CHAOS THEORY; COSMOLOGY; DISTURBANCES; FLUCTUATIONS; INFLATIONARY UNIVERSE; POTENTIALS; SCALE INVARIANCE

Citation Formats

Byrnes, Christian T., and Wands, David. Scale-invariant perturbations from chaotic inflation. United States: N. p., 2006. Web. doi:10.1103/PHYSREVD.73.063509.
Byrnes, Christian T., & Wands, David. Scale-invariant perturbations from chaotic inflation. United States. doi:10.1103/PHYSREVD.73.063509.
Byrnes, Christian T., and Wands, David. Wed . "Scale-invariant perturbations from chaotic inflation". United States. doi:10.1103/PHYSREVD.73.063509.
@article{osti_20782613,
title = {Scale-invariant perturbations from chaotic inflation},
author = {Byrnes, Christian T. and Wands, David},
abstractNote = {Vacuum fluctuations in the inflaton field driving chaotic inflation with a quadratic potential give a red spectrum of primordial density perturbations, n=0.97. However angular fluctuations in an O(N)-symmetric quadratic potential have a very nearly scale-invariant spectrum, n=0.9998. We investigate the possibility that these isocurvature field perturbations could give the dominant contribution to the primordial density perturbation after inflation.},
doi = {10.1103/PHYSREVD.73.063509},
journal = {Physical Review. D, Particles Fields},
number = 6,
volume = 73,
place = {United States},
year = {Wed Mar 15 00:00:00 EST 2006},
month = {Wed Mar 15 00:00:00 EST 2006}
}
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  • Chaotic inflation is analyzed in the frame of scalar-tensor theories of gravity. Fluctuations in the energy density arise from quantum fluctuations of the Brans-Dicke field and of the inflation field. The spectrum of perturbations is studied for a class of models: it is non scale-invarient and, for certain values of the parameters, it has a peak. If the peak appears at astrophysically interesting scales, it may help to reconcile the Cold Dark Matter scenario for structure formation with large scale observations.
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