Baryogenesis in the Inflationary Universe

As is known well, the inflationary universe model resolves most of the fundamental problems concerning the large scale structure of the universe and is now becoming a standard model for the early universe. However, there is one important problem yet to be made clear. In this model the number density of particles effectively goes to zero during the inflation and everything is created after the universe is heated up again at the end of inflation. Since the reheating temperature is much lower than the GUT temperature in general, however, it is not clear whether the observed baryon asymmetry is generated in this process.

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Large Scale Structure of the Universe: Theoretical Problems

Australian Journal of Physics ◽

10.1071/ph900159 ◽

1990 ◽

Vol 43 (2) ◽

pp. 159

Author(s):

E Saar

Keyword(s):

Early Universe ◽

Present Status ◽

Large Scale ◽

Large Scale Structure ◽

Short Review ◽

Fractal Model ◽

Scale Structure ◽

The Subject ◽

The Universe

Implications of the observed large scale structure on the physics of the early universe are described. A short review of Soviet work on the subject is given, and the present status of the fractal model of the large scale structure is discussed.

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Formation Times for Rich Clusters of Galaxies

Publications of the Astronomical Society of Australia ◽

10.1017/s1323358000015113 ◽

1977 ◽

Vol 3 (2) ◽

pp. 140-142 ◽

Cited By ~ 1

Author(s):

B. M. Lewis

Keyword(s):

Gaussian Distribution ◽

Large Scale ◽

Velocity Dispersion ◽

Large Scale Structure ◽

Elliptical Galaxies ◽

Scale Structure ◽

Clusters Of Galaxies ◽

Number Density ◽

Radial Gradient ◽

The Universe

Rich clusters of galaxies are a common feature of the large-scale structure of the Universe. Those studied so far, show striking regularities with (a)a smooth radial gradient of number density.(b)’isothermal’ distributions, which according to Bahcall (1975) have a scatter of only ±15% in the size of their characteristic core radii.(c)their limiting structural diameters are ~50 Mpc (cf. Abell, 1975), if they are identified with superclusters.(d)the magnitude of the velocity dispersion about their centres is generally 600-1000 km s-1, and the velocities are cpnsistent with a gaussian distribution (Yahil and Vidal, 1976; also Faber and Dressier, 1976).(e)The extreme velocities are generally within ±3000 km s-1, and for Coma are ∼2400 km s-1 (Tifft and Gregory, 1976).(f)elliptical galaxies tend to predominate near the centre, spirals in the surrounding loose groups.

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The Fractal Turbulence and the Origin of Large Scale Structure

Symposium - International Astronomical Union ◽

10.1017/s0074180900136824 ◽

1988 ◽

Vol 130 ◽

pp. 553-553

Author(s):

Y.-Z. Liu ◽

Z.-G. Deng

Keyword(s):

Early Universe ◽

Large Scale ◽

Hubble Constant ◽

Large Scale Structure ◽

Thomson Scattering ◽

Scale Structure ◽

Scale Free ◽

Density Perturbations ◽

Reynold’S Number ◽

The Universe

We have suggested a scenario of fractal turbulence which might explain the origin of galaxies and the observed large scale structure of the universe (Liu and Deng, 1987). Under the condition of the early universe, the cosmic fluid can be regarded as incompressible. If we assume that the density perturbations in the early universe are adiabatic and have the scale-free Zeldovich spectrum, we may obtain the spectrum of the velocity perturbations. Perturbations with scales less than horizon will undergo dissipative process by Thomson scattering. So, the cosmic fluid can be considered as a viscous fluid (Peebles, 1971). We can find the largest and smallest scale of the perturbations in the cosmic fluid by taking account of the Reynold's number on given scale and the scale of horizon. Using the present values of Hubble constant and the mean density of matter, we have found that on the scale of horizon the Reynold's number is just the order of 102. This result shows that perturbations with scale a little smaller than horizon may produce Karman vortices before recombination and the vortices might form fractal turbulence due to Thomson drag.

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LARGE SCALE STRUCTURE OF THE UNIVERSE — A POWERFUL PROBE FOR FUNDAMENTAL PHYSICS

International Journal of Modern Physics Conference Series ◽

10.1142/s2010194512006307 ◽

2012 ◽

Vol 12 ◽

pp. 100-109 ◽

Cited By ~ 1

Author(s):

JAAN EINASTO

Keyword(s):

Early Universe ◽

Large Scale ◽

Large Scale Structure ◽

Scale Structure ◽

Fundamental Physics ◽

Sky Surveys ◽

Physical Conditions ◽

Physical Experiments ◽

The Universe

An overview is given on properties of the Large Scale Structure (LSS) using recent sky surveys (SDSS Main sample). LSS evolves very slowly, thus it contains imprints of physical conditions in the early Universe, as well as processes during its evolution. Present physical experiments are still unable to reproduce conditions in the very early Universe, thus the study of the properties of the LSS yields valuable information for fundamental physics.

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Inflation and the Large-Scale Structure of the Universe

Symposium - International Astronomical Union ◽

10.1017/s0074180900135843 ◽

1988 ◽

Vol 130 ◽

pp. 51-62

Author(s):

L.A. Kofman ◽

A.D. Linde ◽

V.F. Mukhanov

Keyword(s):

Large Scale ◽

Large Scale Structure ◽

Scale Structure ◽

Inflationary Universe ◽

Density Perturbations ◽

The Universe

Before the development of the inflationary universe scenario many cosmological problems of the standard hot universe theory remained unsolved. In particular, the origin of primordial density perturbations remained obscure.

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Relativistic Cosmology with an Introduction to Inflation

Universe ◽

10.3390/universe7080276 ◽

2021 ◽

Vol 7 (8) ◽

pp. 276

Author(s):

Muhammad Zahid Mughal ◽

Iftikhar Ahmad ◽

Juan Luis García Guirao

Keyword(s):

Standard Model ◽

Early Universe ◽

Large Scale ◽

Initial Conditions ◽

Big Bang ◽

Relativistic Cosmology ◽

The Standard Model ◽

Big Bang Model ◽

The Big Bang ◽

The Universe

In this review article, the study of the development of relativistic cosmology and the introduction of inflation in it as an exponentially expanding early phase of the universe is carried out. We study the properties of the standard cosmological model developed in the framework of relativistic cosmology and the geometric structure of spacetime connected coherently with it. The geometric properties of space and spacetime ingrained into the standard model of cosmology are investigated in addition. The big bang model of the beginning of the universe is based on the standard model which succumbed to failure in explaining the flatness and the large-scale homogeneity of the universe as demonstrated by observational evidence. These cosmological problems were resolved by introducing a brief acceleratedly expanding phase in the very early universe known as inflation. The cosmic inflation by setting the initial conditions of the standard big bang model resolves these problems of the theory. We discuss how the inflationary paradigm solves these problems by proposing the fast expansion period in the early universe. Further inflation and dark energy in fR modified gravity are also reviewed.

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