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Title: Constraining the variation of G by cosmic microwave background anisotropies

Abstract

We use the Cosmic Microwave Background Anisotropies (CMBA) power spectra to constrain the cosmological variation of gravitational constant G. It is found that the sensitivity of CMBA to the variation of G is enhanced when G is required to converge to its present value. The variations of G from the CMB decoupling epoch z{approx}1000 to the present time are modeled by a step function and a linear function of scale factor a respectively, and the corresponding 95% confidence intervals for G/G{sub 0} are [0.95, 1.05] and [0.89, 1.13], G{sub 0} being the present value. The CMBA constraint is unique in the sense that it entails the range of redshift from z{approx_equal}1000 to 0.

Authors:
;  [1]
  1. Department of Physics and Institute of Theoretical Physics, Chinese University of Hong Kong, Hong Kong (China)
Publication Date:
OSTI Identifier:
21020363
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 8; Other Information: DOI: 10.1103/PhysRevD.75.083521; (c) 2007 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; ANISOTROPY; COSMIC RADIATION; COSMOLOGY; DECOUPLING; ENERGY SPECTRA; FUNDAMENTAL CONSTANTS; RADIOWAVE RADIATION; RELICT RADIATION; SENSITIVITY; VARIATIONS

Citation Formats

Chan, K. C., and Chu, M.-C. Constraining the variation of G by cosmic microwave background anisotropies. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.083521.
Chan, K. C., & Chu, M.-C. Constraining the variation of G by cosmic microwave background anisotropies. United States. doi:10.1103/PHYSREVD.75.083521.
Chan, K. C., and Chu, M.-C. Sun . "Constraining the variation of G by cosmic microwave background anisotropies". United States. doi:10.1103/PHYSREVD.75.083521.
@article{osti_21020363,
title = {Constraining the variation of G by cosmic microwave background anisotropies},
author = {Chan, K. C. and Chu, M.-C.},
abstractNote = {We use the Cosmic Microwave Background Anisotropies (CMBA) power spectra to constrain the cosmological variation of gravitational constant G. It is found that the sensitivity of CMBA to the variation of G is enhanced when G is required to converge to its present value. The variations of G from the CMB decoupling epoch z{approx}1000 to the present time are modeled by a step function and a linear function of scale factor a respectively, and the corresponding 95% confidence intervals for G/G{sub 0} are [0.95, 1.05] and [0.89, 1.13], G{sub 0} being the present value. The CMBA constraint is unique in the sense that it entails the range of redshift from z{approx_equal}1000 to 0.},
doi = {10.1103/PHYSREVD.75.083521},
journal = {Physical Review. D, Particles Fields},
number = 8,
volume = 75,
place = {United States},
year = {Sun Apr 15 00:00:00 EDT 2007},
month = {Sun Apr 15 00:00:00 EDT 2007}
}
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