53 research outputs found
Natural Inflation, Planck Scale Physics and Oscillating Primordial Spectrum
In the ``natural inflation'' model, the inflaton potential is periodic. We
show that Planck scale physics may induce corrections to the inflaton
potential, which is also periodic with a greater frequency. Such high frequency
corrections produce oscillating features in the primordial fluctuation power
spectrum, which are not entirely excluded by the current observations and may
be detectable in high precision data of cosmic microwave background (CMB)
anisotropy and large scale structure (LSS) observations.Comment: 20 pages, 11 figures. To appear in Int J Mod. Phys.
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
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.
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
Reconstructing large running-index inflaton potentials
Recent fits of cosmological parameters by the first year Wilkinson Microwave
Anisotropy Probe (WMAP) measurement seem to favor a primordial scalar spectrum
with a large varying index from blue to red. We use the inflationary flow
equations to reconstruct large running-index inflaton potentials and comment on
current status on the inflationary flow. We find previous negligence of higher
order slow rolling contributions when using the flow equations would lead to
unprecise results.Comment: Final version to appear in Class. Quant. Grav. References adde
The chromosome-level quality genome provides insights into the evolution of the biosynthesis genes for aroma compounds of Osmanthus fragrans
Genome sequences: Discovering a sweet secret A high-quality genome sequence for sweet olive, Osmanthus fragrans, has revealed which genes make the ornamental tree’s blossoms so fragrant. Lianggui Wang at Nanjing Forestry University in China and coworkers used cutting-edge approaches to produce a high-resolution picture of sweet olive’s genome. Analysis of the full sequence revealed that sweet olive has a large number of genes, more than 45,000. Further investigation showed that the entire genome had been duplicated, or accidentally copied, several million years ago. Thanks to the duplication, sweet olive has extra copies of the genes that produce its scent compound, resulting in its very strong scent. These results are only the beginning. Having this first sequence makes sequencing other varieties of sweet olive much easier, and future comparisons between genomes will help to pinpoint genes that control many other traits
Author Correction: The chromosome-level quality genome provides insights into the evolution of the biosynthesis genes for aroma compounds of Osmanthus fragrans
Since the publication of this article, the authors have noticed that the NCBI accession number is missing from article
Assessing shale gas resources of Wufeng-Longmaxi shale (O3w-S1l) in Jiaoshiba area, SE Sichuan (China) using Petromod II: Gas generation and adsorption
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