23 research outputs found
Cosmological Evolution of Interacting Dark Energy Models with Mass Varying Neutrinos
In this paper we consider the cosmological implications of dark energy models
with a coupled system of a dynamical scalar field (the quintessence) and the
neutrinos. By detailed numerical calculations we study the various
possibilities on the evolution and the fates of the universe in this class of
models. Our results show that due to the interaction with quintessence,
neutrinos could be dominant over the quintessence in the future universe,
however would eventually decay away.Comment: One typographical error corrected, references updated and
presentation improve
Curvaton Reheating in Non-oscillatory Inflationary Models
In non-oscillatory (NO) inflationary models, the reheating mechanism was
usually based on gravitational particle production or the mechanism of instant
preheating. In this paper we introduce the curvaton mechanism into NO models to
reheat the universe and generate the curvature perturbation. Specifically we
consider the Peebles-Vilenkin quintessential inflation model, where the
reheating temperature can be extended from 1MeV to GeV.Comment: 4 pages, 1 figur
K-essential Leptogenesis
K-essence is a possible candidate for dark energy of the Universe. In this
paper we consider couplings of k-essence to the matter fields of the standard
electroweak theory and study the effects of the cosmological CPT violation
induced by the CPT violating {\bf Ether} during the evolution of the k-essence
scalar field on the laboratory experiments and baryogenesis. Our results show
that the matter and antimatter asymmetry can be naturally explained {\it via}
leptogenesis without conflicting with the experimental limits on CPT violation
test. The mechanism for baryogenesis proposed in this paper provides a unified
picture for dark energy and baryon matter of our Universe and allows an almost
degenerate neutrino mass pattern with a predicted rate on the neutrinoless
double beta decays accessible to the experimental sensitivity in the near
future.Comment: 6 pages, 1 figure. To appear in Phys. Lett.
Dark Energy and Neutrino Mass Limits from Baryogenesis
In this brief report we consider couplings of the dark energy scalar, such as
Quintessence to the neutrinos and discuss its implications in studies on the
neutrino mass limits from Baryogenesis. During the evolution of the dark energy
scalar, the neutrino masses vary, consequently the bounds on the neutrino
masses we have here differ from those obtained before.Comment: 5 pages,3 figures. Version accepted for publication in Phys. Rev.
Cosmological Models with Fractional Derivatives and Fractional Action Functional
Cosmological models of a scalar field with dynamical equations containing
fractional derivatives or derived from the Einstein-Hilbert action of
fractional order, are constructed. A number of exact solutions to those
equations of fractional cosmological models in both cases is given.Comment: 14 page
Fermionic partner of Quintessence field as candidate for dark matter
Quintessence is a possible candidate for dark energy. In this paper we study
the phenomenologies of the fermionic partner of Quintessence, the Quintessino.
Our results show that, for suitable choices of the model parameters, the
Quintessino is a good candidate for cold or warm dark matter. In our scenario,
dark energy and dark matter of the Universe are connected in one chiral
superfield.Comment: 4 pages, 3 figures, version to appear in PR
Quintessence and Spontaneous Leptogenesis
We propose in this paper a scenario of spontaneous baryogenesis in
cosmological models of Quintessence by introducing a derivative coupling of the
Quintessence scalar to the baryon current or the current of the
baryon number minus lepton number . We find that with a
dimension-5 operator suppressed by the Planck
mass or the Grand Unification Scale , baryon number asymmetry
can be naturally explained {\it via} leptogenesis. We
study also the isocurvature baryon number fluctuation generated in our model.Comment: 7pages,1figur
Vitamin E-modified filters modulate Jun N-terminal kinase activation in peripheral blood mononuclear cells
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Dark Energy and Neutrino CPT Violation
In this paper we study the dynamical CPT violation in the neutrino sector
induced by the dark energy of the Universe. Specifically we consider a dark
energy model where the dark energy scalar derivatively interacts with the
right-handed neutrinos. This type of derivative coupling leads to a
cosmological CPT violation during the evolution of the background field of the
dark energy. We calculate the induced CPT violation of left-handed neutrinos
and find the CPT violation produced in this way is consistent with the present
experimental limit and sensitive to the future neutrino oscillation
experiments, such as the neutrino factory.Comment: 10 pages, 2 figures. Typos corrected and references added. To be
published in EPJ
Thermal leptogenesis in a model with mass varying neutrinos
In this paper we consider the possibility of neutrino mass varying during the
evolution of the Universe and study its implications on leptogenesis.
Specifically, we take the minimal seesaw model of neutrino masses and introduce
a coupling between the right-handed neutrinos and the dark energy scalar field,
the Quintessence. In our model, the right-handed neutrino masses change as the
Quintessence scalar evolves. We then examine in detail the parameter space of
this model allowed by the observed baryon number asymmetry. Our results show
that it is possible to lower the reheating temperature in this scenario in
comparison with the case that the neutrino masses are unchanged, which helps
solve the gravitino problem. Furthermore, a degenerate neutrino mass patten
with larger than the upper limit given in the minimal leptogenesis
scenario is permitted.Comment: 18 pages, 7 figures, version to appear in PR