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 angulardiameter distance to the CMB lastscattering surface, which is also affected by dark energy, they are limited by our understanding of the dark energy. Measurements of luminosity or angulardiameter distances to redshifts in the matterdominated 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 superHubble scales.
 Authors:
 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 angulardiameter distance to the CMB lastscattering surface, which is also affected by dark energy, they are limited by our understanding of the dark energy. Measurements of luminosity or angulardiameter distances to redshifts in the matterdominated 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 superHubble 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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