搜索结果: 1-14 共查到“天文学 Curvature”相关记录14条 . 查询时间(0.296 秒)
Constraining dynamical dark energy with a divergence-free parametrization in the presence of spatial curvature and massive neutrinos
Constraining dynamical dark energy divergence-free parametrization presence spatial curvature massive neutrinos
2012/2/21
In this paper, we report the results of constraining the dynamical dark energy with a divergence-free parameterization, $w(z) = w_{0} + w_{a}(\frac{\ln(2+z)}{1+z}-\ln2)$, in the presence of spatial cu...
Graphic solution of R-W metric for the case of positive curvature and cosmic entire space and time
R-W metric hypersphere cosmology large scale structure of the universe space and time absolutism relativism
2011/9/26
The vivid image of R-W metric for the case of hypersphere is given; The hypersphere is proposed as the only model for the physical universe; The cosmic radius R(t) may be defined as a cosmic broad tim...
Curvature perturbation from velocity modulation
Curvature perturbation velocity modulation
2011/10/9
We propose a new variant model of the modulated reheating. If particles have large scale fluctuations on their velocities, or equivalently their Lorentz factors, the decay rate also fluctuates and the...
Local Scale-Dependent Non-Gaussian Curvature Perturbations at Cubic Order
Eective Field Theory Cosmology In ation Non-Gaussianity
2011/10/17
We calculate non-Gaussianities in the bispectrum and trispectrum arising from the cubic term in the local expansion of the scalar curvature perturbation. We compute to three-loop order and for general...
Curvature perturbation spectra from waterfall transition, black hole constraints and non-Gaussianity
waterfall transition black hole constraints non-Gaussianity
2011/10/11
We carried out numerical calculations of a contribution of the waterfall field to the primordial curvature perturbation (on uniform density hypersurfaces) $\zeta$, which is produced during waterfall t...
Feynman-like Rules for Calculating n-Point Correlators of the Primordial Curvature Perturbation
ing n-Point Correlators Primordial Curvature Perturbation
2011/10/10
A diagrammatic approach to calculate n-point correlators of the primordial curvature perturbation \zeta was developed a few years ago following the spirit of the Feynman rules in Quantum Field Theory....
Conformal invariance of curvature perturbation
Conformal invariance curvature perturbation
2011/10/18
We show that in the single component situation all perturbation variables in the comoving gauge are conformally invariant to all perturbation orders. Generally we identify a special time slicing, the ...
Cosmological Perturbation Theory With Background Anisotropic Curvature
Cosmological Perturbation Theory Background Anisotropic Curvature
2011/10/18
The theory of cosmological perturbations is extended to spacetimes displaying isotropic expansion but anisotropic curvature. The perturbed Einstein equation and Boltzmann equations for massless and ma...
Curvature Perturbations and non-Gaussianities from Waterfall Phase Transition during Inflation
Curvature Perturbations non-Gaussianities
2011/1/13
We consider a variant of hybrid inflation where the waterfall phase transition happens during inflation. By adjusting the parameters associated with the mass of the waterfall field, we arrange that t...
Evidence of major dry mergers at M* > 2 x 10^11 Msun from curvature in early-type galaxy scaling relations?
galaxies formation
2010/11/11
For early-type galaxies, the correlations between stellar mass and size, velocity dis-
persion, surface brightness, color, axis ratio and color-gradient all indicate that two mass scales, M∗ = ...
Observational constraints on Chaplygin cosmology in a braneworld scenario with induced gravity and curvature effect
Cosmology Dark energy -Cosmology theory- Cosmology Observations
2010/11/16
We study cosmological dynamics and late-time evolution of an extended induced grav-ity braneworld scenario. In this scenario, curvature effects are taken into account via the
Gauss-Bonnet term in the...
Waterfall field in hybrid inflation and curvature perturbation
Cosmology and Extragalactic Astrophysics (astro-ph.CO)
2011/1/6
We study carefully the contribution of the waterfall field to the curvature perturbation at the end of hybrid inflation. In particular we clarify the parameter dependence analytically under reasonable...
The effect of curvature in thawing models
Cosmology and Extragalactic Astrophysics (astro-ph.CO) General Relativity and Quantum Cosmology (gr-qc)
2010/12/29
We study the evolution of spatial curvature for thawing class of dark energy models. We examine the evolution of the equation of state parameter, $w_\phi$, as a function of the scale factor $a$, for t...
The Curvature Wavefront Sensor of the Guieloa Adaptive Optics System
Curvature Wavefront Sensor Guieloa Adaptive Optics System
2009/7/1
The Curvature Wavefront Sensor of the Guieloa Adaptive Optics System。