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Title: Cosmology of mass-varying neutrinos driven by quintessence: Theory and observations

Abstract

The effects of mass-varying 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 mass-varying 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 wide-ranging 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 » some evidence that the existence of such a coupling is actually preferred by current cosmological data over the standard {lambda}CDM cosmology.« less

Authors:
 [1];  [2];  [3];  [4]
  1. Department of Applied Mathematics and Department of Physics, Astro-Particle Theory Cosmology Group, Hounsfield Road, Hicks Building, University of Sheffield, Sheffield S3 7RH (United Kingdom)
  2. Department of Applied Mathematics, Astro-Particle Theory Cosmology Group, Hounsfield Road, Hicks Building, University of Sheffield, Sheffield S3 7RH (United Kingdom)
  3. Institute of Theoretical Astrophysics, University of Oslo, 0315 Oslo (Norway)
  4. 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 Tocchini-Valentini, D. Cosmology of mass-varying 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., & Tocchini-Valentini, D. Cosmology of mass-varying 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 Tocchini-Valentini, D. Sat . "Cosmology of mass-varying neutrinos driven by quintessence: Theory and observations". United States. doi:10.1103/PHYSREVD.73.083515.
@article{osti_20782886,
title = {Cosmology of mass-varying neutrinos driven by quintessence: Theory and observations},
author = {Brookfield, A.W. and Bruck, C. van de and Mota, D.F. and Tocchini-Valentini, D.},
abstractNote = {The effects of mass-varying 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 mass-varying 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 wide-ranging 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}
}
  • No abstract prepared.
  • We analyze the mass varying neutrino scenario. We consider a minimal model of massless Dirac fermions coupled to a scalar field, mainly in the framework of finite-temperature quantum field theory. We demonstrate that the mass equation we find has nontrivial solutions only for special classes of potentials, and only within certain temperature intervals. We give most of our results for the Ratra-Peebles dark energy (DE) potential. The thermal (temporal) evolution of the model is analyzed. Following the time arrow, the stable, metastable, and unstable phases are predicted. The model predicts that the present Universe is below its critical temperature andmore » accelerates. At the critical point, the Universe undergoes a first-order phase transition from the (meta)stable oscillatory regime to the unstable rolling regime of the DE field. This conclusion agrees with the original idea of quintessence as a force making the Universe roll towards its true vacuum with a zero {Lambda} term. The present mass varying neutrino scenario is free from the coincidence problem, since both the DE density and the neutrino mass are determined by the scale M of the potential. Choosing M{approx}10{sup -3} eV to match the present DE density, we can obtain the present neutrino mass in the range m{approx}10{sup -2}-1 eV and consistent estimates for other parameters of the Universe.« less
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  • We analyze the constraints on neutrino mass spectra with extra sterile neutrinos as implied by the LSND experiment. The various mass related observables in neutrinoless double beta decay, tritium beta decay and cosmology are discussed. Both neutrino oscillation results as well as recent cosmological neutrino mass bounds are taken into account. We find that some of the allowed mass patterns are severely restricted by the current constraints, in particular, by the cosmological constraints on the total sum of neutrino masses and by the nonmaximality of the solar neutrino mixing angle. Furthermore, we estimate the form of the four neutrino massmore » matrices and also comment on the situation in scenarios with two additional sterile neutrinos.« less