Cosmology of massvarying neutrinos driven by quintessence: Theory and observations
Abstract
The effects of massvarying neutrinos on cosmic microwave background (CMB) anisotropies and large scale structures (LSS) are studied. In these models, dark energy and neutrinos are coupled such that the neutrino masses are functions of the scalar field playing the role of dark energy. We begin by describing the cosmological background evolution of such a system. It is pointed out that, similar to models with a dark matter/dark energy interaction, the apparent equation of state measured with SNIa can be smaller than 1. We then discuss the effect of massvarying neutrinos on the CMB anisotropies and the matter power spectrum. A suppression of power in the CMB power spectrum at large angular scales is usually observed. We give an explanation for this behavior and discuss different couplings and quintessence potentials to show the generality of the results obtained. We perform a likelihood analysis using wideranging SNIa, CMB, and LSS observations to assess whether such theories are viable. Treating the neutrino mass as a free parameter we find that the constraints on the coupling are weak, since CMB and LSS surveys give only upper bounds on the neutrino mass. However, fixing a priori the neutrino masses, we find that there ismore »
 Authors:
 Department of Applied Mathematics and Department of Physics, AstroParticle Theory Cosmology Group, Hounsfield Road, Hicks Building, University of Sheffield, Sheffield S3 7RH (United Kingdom)
 Department of Applied Mathematics, AstroParticle Theory Cosmology Group, Hounsfield Road, Hicks Building, University of Sheffield, Sheffield S3 7RH (United Kingdom)
 Institute of Theoretical Astrophysics, University of Oslo, 0315 Oslo (Norway)
 Astrophysics Department, Oxford University, Keble Road, Oxford OX1 3RH (United Kingdom) and Department of Physics and Astronomy, The Johns Hopkins University, Baltimore, Maryland 21218 (United States)
 Publication Date:
 OSTI Identifier:
 20782886
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. D, Particles Fields; Journal Volume: 73; Journal Issue: 8; Other Information: DOI: 10.1103/PhysRevD.73.083515; (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; COSMIC NEUTRINOS; COSMOLOGY; COUPLING; ENERGY SPECTRA; EQUATIONS OF STATE; NONLUMINOUS MATTER; POTENTIALS; RADIOWAVE RADIATION; RELICT RADIATION; REST MASS; SCALAR FIELDS; SUPERNOVAE
Citation Formats
Brookfield, A.W., Bruck, C. van de, Mota, D.F., and TocchiniValentini, D. Cosmology of massvarying neutrinos driven by quintessence: Theory and observations. United States: N. p., 2006.
Web. doi:10.1103/PHYSREVD.73.083515.
Brookfield, A.W., Bruck, C. van de, Mota, D.F., & TocchiniValentini, D. Cosmology of massvarying neutrinos driven by quintessence: Theory and observations. United States. doi:10.1103/PHYSREVD.73.083515.
Brookfield, A.W., Bruck, C. van de, Mota, D.F., and TocchiniValentini, D. Sat .
"Cosmology of massvarying neutrinos driven by quintessence: Theory and observations". United States.
doi:10.1103/PHYSREVD.73.083515.
@article{osti_20782886,
title = {Cosmology of massvarying neutrinos driven by quintessence: Theory and observations},
author = {Brookfield, A.W. and Bruck, C. van de and Mota, D.F. and TocchiniValentini, D.},
abstractNote = {The effects of massvarying neutrinos on cosmic microwave background (CMB) anisotropies and large scale structures (LSS) are studied. In these models, dark energy and neutrinos are coupled such that the neutrino masses are functions of the scalar field playing the role of dark energy. We begin by describing the cosmological background evolution of such a system. It is pointed out that, similar to models with a dark matter/dark energy interaction, the apparent equation of state measured with SNIa can be smaller than 1. We then discuss the effect of massvarying neutrinos on the CMB anisotropies and the matter power spectrum. A suppression of power in the CMB power spectrum at large angular scales is usually observed. We give an explanation for this behavior and discuss different couplings and quintessence potentials to show the generality of the results obtained. We perform a likelihood analysis using wideranging SNIa, CMB, and LSS observations to assess whether such theories are viable. Treating the neutrino mass as a free parameter we find that the constraints on the coupling are weak, since CMB and LSS surveys give only upper bounds on the neutrino mass. However, fixing a priori the neutrino masses, we find that there is some evidence that the existence of such a coupling is actually preferred by current cosmological data over the standard {lambda}CDM cosmology.},
doi = {10.1103/PHYSREVD.73.083515},
journal = {Physical Review. D, Particles Fields},
number = 8,
volume = 73,
place = {United States},
year = {Sat Apr 15 00:00:00 EDT 2006},
month = {Sat Apr 15 00:00:00 EDT 2006}
}

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