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Title: Precision measurement of the mean curvature

Abstract

Very small mean curvature is a robust prediction of inflation worth rigorous checking. Since current constraints are derived from determinations of the angular-diameter distance to the CMB last-scattering surface, which is also affected by dark energy, they are limited by our understanding of the dark energy. Measurements of luminosity or angular-diameter distances to redshifts in the matter-dominated era can greatly reduce this uncertainty. With a 1% measurement of the distance to z=3, combined with the CMB data expected from Planck, one can achieve {sigma}({omega}{sub k}h{sup 2}){approx}10{sup -3}. A nonzero detection at this level would be evidence against inflation or for unusually large curvature fluctuations on super-Hubble scales.

Authors:
 [1]
  1. Department of Physics, University of California, One Shields Avenue, Davis, California 95616 (United States)
Publication Date:
OSTI Identifier:
20795695
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 73; Journal Issue: 2; Other Information: DOI: 10.1103/PhysRevD.73.023503; (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; ACCURACY; COSMIC RADIATION; COSMOLOGY; DETECTION; DISTANCE; FLUCTUATIONS; INFLATIONARY UNIVERSE; NONLUMINOUS MATTER; RADIOWAVE RADIATION; RELICT RADIATION; SCATTERING

Citation Formats

Knox, Lloyd. Precision measurement of the mean curvature. United States: N. p., 2006. Web. doi:10.1103/PHYSREVD.73.0.
Knox, Lloyd. Precision measurement of the mean curvature. United States. doi:10.1103/PHYSREVD.73.0.
Knox, Lloyd. Sun . "Precision measurement of the mean curvature". United States. doi:10.1103/PHYSREVD.73.0.
@article{osti_20795695,
title = {Precision measurement of the mean curvature},
author = {Knox, Lloyd},
abstractNote = {Very small mean curvature is a robust prediction of inflation worth rigorous checking. Since current constraints are derived from determinations of the angular-diameter distance to the CMB last-scattering surface, which is also affected by dark energy, they are limited by our understanding of the dark energy. Measurements of luminosity or angular-diameter distances to redshifts in the matter-dominated era can greatly reduce this uncertainty. With a 1% measurement of the distance to z=3, combined with the CMB data expected from Planck, one can achieve {sigma}({omega}{sub k}h{sup 2}){approx}10{sup -3}. A nonzero detection at this level would be evidence against inflation or for unusually large curvature fluctuations on super-Hubble scales.},
doi = {10.1103/PHYSREVD.73.0},
journal = {Physical Review. D, Particles Fields},
number = 2,
volume = 73,
place = {United States},
year = {Sun Jan 15 00:00:00 EST 2006},
month = {Sun Jan 15 00:00:00 EST 2006}
}
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