Results 41 to 50 of about 17,761 (262)
The Basics of Flat Space Cosmology
International Journal of Astronomy and Astrophysics, 2015 We present a new model of cosmology which appears to show great promise. Our flat space cosmology model, using only four basic and reasonable assumptions, derives highly accurate Hubble parameter H0, Hubble radius R0 and total mass M0 values for our observable universe.
Eugene Terry Tatum +2 more
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UNIVERSE EVOLUTION IN A 5D RICCI-FLAT COSMOLOGY [PDF]
Modern Physics Letters A, 2006 We use Wetterich's parametrization equation of state (EOS) of dark energy to a 5D Ricci-flat cosmological solution and we assume that the universe contains three major components: matter, radiation and dark energy. By using the relation between the scale factor and the redshift z, we show that the two arbitrary functions contained in the 5D solution ...
Zhang, Chengwu +3 more
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, 1994 These lectures provide an introductory review of big bang cosmology. I discuss the expanding Friedmann-Robertson-Walker universe, summarizing the observational evidence which has led to its adoption as the `standard' cosmological model and reviewing its ...
Frieman, Josh
core +1 more source
GRAVITATIONAL LENSING CORRECTIONS IN FLAT ΛCDM COSMOLOGY [PDF]
The Astrophysical Journal, 2010 20 pages, 4 figures, ApJ in ...
Kantowski, Ronald, Chen, Bin, Dai, Xinyu
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Bouncing Loop Quantum Cosmology from $F(T)$ gravity [PDF]
, 2013 The big bang singularity could be understood as a breakdown of Einstein's General Relativity at very high energies. Adopting this viewpoint, other theories, that implement Einstein Cosmology at high energies, might solve the problem of the primeval ...
Amorós, Jaume +2 more
core +3 more sources
Pre-Big-Bang Requires the Universe to be Exponentially Large From the Very Beginning [PDF]
, 1998 We show that in a generic case of the pre-big-bang scenario, inflation will solve cosmological problems only if the universe at the onset of inflation is extremely large and homogeneous from the very beginning.
A. Buonanno +37 more
core +2 more sources
Voronoi Chords in Flat Cosmology
Advances in Astrophysics, 2017 In this paper we present formulae for chord length distribution in the framework of Poissonian Voronoi Tessellation (PVT) and non Poissonian Voronoi Tessellation (NPVT). The introduction of the scale parameter in the obtained distributions allows us to model the chord for cosmic voids. A graphical comparison between cosmic voids visible on two catalogs
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Holography for the very early Universe and the classic puzzles of Hot Big Bang cosmology
, 2019 We show that standard puzzles of hot Big Bang cosmology that motivated the introduction of cosmological inflation, such as the smoothness and horizon problem, the flatness problem and the relic problem are also solved by holographic models for very early
Nastase, Horatiu, Skenderis, Kostas
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Variable-Speed-of-Light Cosmology and Second Law of Thermodynamics [PDF]
, 2002 We examine whether the cosmologies with varying speed of light (VSL) are compatible with the second law of thermodynamics. We find that the VSL cosmology with varying fundamental constant is severely constrained by the second law of thermodynamics ...
A. Albrecht +28 more
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Archaeological Prospection, EarlyView.ABSTRACT In Upper Mesopotamia, the transition from the Pre‐Pottery Neolithic A (PPNA) to Pre‐Pottery Neolithic B (PPNB) period, ca. 10 800–10 600 cal. BP, is marked by a series of changes in chipped stone industries, architectural forms, symbolic objects, regional distribution of settlements and long‐distance exchange networks among others.
Toshihiro Tada +7 more
wiley +1 more source