Big bang nucleosynthesis constraints on universal extra dimensions and varying fundamental constants
Abstract
The successful prediction of light element abundances from big bang nucleosynthesis (BBN) has been a pillar of the standard model of cosmology. Because many of the relevant reaction rates are sensitive to the values of fundamental constants, such as the fine structure constant and the strong coupling constant, BBN is a useful tool to probe and to put constraints on possible cosmological variations of these constants, which arise naturally from many versions of extradimensional theories. In this paper, we study the dependences of fundamental constants on the radion field of the universal extradimension model, and calculate the effects of such varying constants on BBN. We also discuss the possibility that the discrepancy between BBN and the Wilkinson Microwave Anisotropy Probe (WMAP) data on the baryontophoton ratio can be reduced if the volume of the extra dimensions was slightly largerby O(10{sup 3})at the BBN era compared to its present value, which would result in smaller gauge couplings at BBN by the same factor.
 Authors:
 Department of Physics, Chinese University of Hong Kong, Hong Kong (China)
 Publication Date:
 OSTI Identifier:
 20795748
 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.73.025004; (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; ANISOTROPY; BARYONS; COSMOLOGY; ELEMENT ABUNDANCE; FINE STRUCTURE; FUNDAMENTAL CONSTANTS; NUCLEAR REACTION KINETICS; NUCLEOSYNTHESIS; PHOTONS; RELICT RADIATION; STANDARD MODEL; STRONGCOUPLING MODEL; VARIATIONS
Citation Formats
Li, B., and Chu, M.C. Big bang nucleosynthesis constraints on universal extra dimensions and varying fundamental constants. United States: N. p., 2006.
Web. doi:10.1103/PHYSREVD.73.0.
Li, B., & Chu, M.C. Big bang nucleosynthesis constraints on universal extra dimensions and varying fundamental constants. United States. doi:10.1103/PHYSREVD.73.0.
Li, B., and Chu, M.C. Sun .
"Big bang nucleosynthesis constraints on universal extra dimensions and varying fundamental constants". United States.
doi:10.1103/PHYSREVD.73.0.
@article{osti_20795748,
title = {Big bang nucleosynthesis constraints on universal extra dimensions and varying fundamental constants},
author = {Li, B. and Chu, M.C.},
abstractNote = {The successful prediction of light element abundances from big bang nucleosynthesis (BBN) has been a pillar of the standard model of cosmology. Because many of the relevant reaction rates are sensitive to the values of fundamental constants, such as the fine structure constant and the strong coupling constant, BBN is a useful tool to probe and to put constraints on possible cosmological variations of these constants, which arise naturally from many versions of extradimensional theories. In this paper, we study the dependences of fundamental constants on the radion field of the universal extradimension model, and calculate the effects of such varying constants on BBN. We also discuss the possibility that the discrepancy between BBN and the Wilkinson Microwave Anisotropy Probe (WMAP) data on the baryontophoton ratio can be reduced if the volume of the extra dimensions was slightly largerby O(10{sup 3})at the BBN era compared to its present value, which would result in smaller gauge couplings at BBN by the same factor.},
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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