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Early star-forming galaxies and the reionization of the Universe
Early star-forming galaxies reionization of the Universe
2010/11/10
Star forming galaxies represent a valuable tracer of cosmic history. Recent observational progress with Hubble Space Telescope has led to the discovery and study of the earliest-known galaxies corresp...
A Series Solution to the Luminosity Distance in a Flat LCDM Universe
Cosmological distances Numerical methods
2010/11/15
Cosmological observations indicate that our universe is flat and dark energy (DE)
dominated at present. The luminosity distance plays an important role in the investigation
of the evolution and stru...
Cosmological observations on the largest scales exhibit a solid record of unexpected anomalies and alignments, apparently pointing towards a large scale violation of statistical isotropy. These includ...
Propagation of the burst of radiation in expanding and recombining Universe: Thomson scattering
radiation expanding recombining Universe
2011/1/10
Within the framework of a flat cosmological model a propagation of an instantaneous burst of nonpolarized isotropic radiation is considered from the moment of its beginning at some initial redshift z0...
Constraints on the Dark Side of the Universe and Observational Hubble Parameter Data
Cosmology and Extragalactic Astrophysics (astro-ph.CO)
2010/12/27
This paper is a review on the observational Hubble parameter data that have gained increasing attention in recent years for their illuminating power on the dark side of the universe --- the dark matte...
The Accelerating Universe
Cosmology and Extragalactic Astrophysics (astro-ph.CO) Popular Physics (physics.pop-ph)
2010/12/24
In this article we review the discovery of the accelerating universe using type Ia supernovae. We then outline ways in which dark energy - component that causes the acceleration - is phenomenologicall...
Constraining the expansion rate of the Universe using low-redshift ellipticals as cosmic chronometers
Cosmology and Extragalactic Astrophysics (astro-ph.CO)
2010/12/24
We present a new methodology to determine the expansion history of the Universe analyzing the spectral properties of early type galaxies (ETG). We found that for these galaxies the 4000\AA break is a ...
Energy in an Expanding Universe in the Teleparallel Geometry
Gravitation teleparallelism gravitational energy- momentum tensor
2010/6/30
The main purpose of this paper is to explicitly verify the consistency of the energy-momentum and angular momentum tensor of the gravitational field established in the Hamiltonian structure of the Tel...
Mysterious 'dark flow' at the edge of the universe（图）
'dark flow' the edge of the universe
2010/3/26
Astronomers have found that whole clusters of galaxies are moving in convoy towards a single point in the sky. This unexpected motion appears to be separate from the expansion of the universe and the ...
Whether life exists elsewhere in our universe is a longstanding mystery. But for some scientists, there’s another interesting question: could there be life in a universe significantly different from o...
Gravitational Charged Perfect Fluid Collapse in Friedmann Universe Models
Electric field Gravitational collapse Cosmological constant Friedmann models
2010/3/18
This paper is devoted to study the gravitational charged perfect fluid collapse in the Friedmann universe models with cosmological constant. For this purpose, we assume that the electromagnetic field ...
A universe much like the (Euclidean) de Sitter space-time appears as background geometry in the causal dynamical triangulation (CDT) regularization of quantum gravity. We study the geometry of such un...
Varying couplings in the early universe: correlated variations of $\alpha$ and $G$
early universe Planck satellite mission
2010/3/19
The Cosmic Microwave Background anisotropies provide a unique opportunity to constrain simultaneous variations of the fine-structure constant $\alpha$ and Newton's gravitational constant $G$. Those co...
We present a holographic description of four-dimensional single-scalar inflationary universes in terms of a three-dimensional quantum field theory. The holographic description correctly reproduces sta...
NASA's New Museum Grant Allies Will Make the Universe Accessible to Families From Alaska to Florida
NASA's New Museum Grant Allies the Universe Families Alaska Florida
2010/1/19
Interactive museum exhibits about climate change, Earth science, and missions beyond Earth are among the projects NASA has selected to receive agency funding. Nine informal education providers from Al...