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Title: Primordial non-Gaussianity and gravitational waves: Observational tests of brane inflation in string theory

Abstract

We study brane inflation scenarios in a warped throat geometry and show that there exists a consistency condition between the non-Gaussianity of the curvature perturbation and the amplitude and scale-dependence of the primordial gravitational waves. This condition is independent of the warping of the throat and the form of the inflaton potential. We find that such a relation could be tested by a future CMB polarization experiment if the Planck satellite is able to detect both a gravitational wave background and a non-Gaussian statistic. In models where the observable stage of inflation occurs when the brane is in the tip region of the throat, we derive a further consistency condition involving the scalar spectral index, the tensor-scalar ratio and the curvature perturbation bispectrum. We show that when such a relation is combined with the WMAP3 results, it leads to a model-independent bound on the gravitational wave amplitude given by 10{sup -3}<r<10{sup -2}. This corresponds to the range of sensitivity of the next generation of CMB polarization experiments.

Authors:
;  [1]
  1. Astronomy Unit, School of Mathematical Sciences, Queen Mary, University of London, Mile End Road, London, E1 4NS (United Kingdom)
Publication Date:
OSTI Identifier:
21011048
Resource Type:
Journal Article
Journal Name:
Physical Review. D, Particles Fields
Additional Journal Information:
Journal Volume: 75; Journal Issue: 4; Other Information: DOI: 10.1103/PhysRevD.75.043505; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0556-2821
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; AMPLITUDES; BRANES; COSMIC RADIATION; COSMOLOGY; DISTURBANCES; GRAVITATION; GRAVITATIONAL WAVES; POLARIZATION; POTENTIALS; RELICT RADIATION; SENSITIVITY; STRING MODELS; TENSORS

Citation Formats

Lidsey, James E, and Seery, David. Primordial non-Gaussianity and gravitational waves: Observational tests of brane inflation in string theory. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.043505.
Lidsey, James E, & Seery, David. Primordial non-Gaussianity and gravitational waves: Observational tests of brane inflation in string theory. United States. doi:10.1103/PHYSREVD.75.043505.
Lidsey, James E, and Seery, David. Thu . "Primordial non-Gaussianity and gravitational waves: Observational tests of brane inflation in string theory". United States. doi:10.1103/PHYSREVD.75.043505.
@article{osti_21011048,
title = {Primordial non-Gaussianity and gravitational waves: Observational tests of brane inflation in string theory},
author = {Lidsey, James E and Seery, David},
abstractNote = {We study brane inflation scenarios in a warped throat geometry and show that there exists a consistency condition between the non-Gaussianity of the curvature perturbation and the amplitude and scale-dependence of the primordial gravitational waves. This condition is independent of the warping of the throat and the form of the inflaton potential. We find that such a relation could be tested by a future CMB polarization experiment if the Planck satellite is able to detect both a gravitational wave background and a non-Gaussian statistic. In models where the observable stage of inflation occurs when the brane is in the tip region of the throat, we derive a further consistency condition involving the scalar spectral index, the tensor-scalar ratio and the curvature perturbation bispectrum. We show that when such a relation is combined with the WMAP3 results, it leads to a model-independent bound on the gravitational wave amplitude given by 10{sup -3}<r<10{sup -2}. This corresponds to the range of sensitivity of the next generation of CMB polarization experiments.},
doi = {10.1103/PHYSREVD.75.043505},
journal = {Physical Review. D, Particles Fields},
issn = {0556-2821},
number = 4,
volume = 75,
place = {United States},
year = {2007},
month = {2}
}