Interpretation of anisotropy in the cosmic background radiation

1982 ◽  
Vol 307 (1497) ◽  
pp. 97-110 ◽  
Keyword(s):  
Galaxy Formation ◽  
Large Scale ◽  
Background Radiation ◽  
Cosmic Background Radiation ◽  
Microwave Background ◽  
Cosmic Background ◽  
Microwave Background Radiation

We review mechanisms for producing temperature and polarization anisotropies in the microwave background radiation, and summarize their relation to the large-scale distribution of matter and to theories of galaxy formation. We also review possible sources of ambiguity in interpreting data, in particular the unknown opacity of the pregalactic gas and the possible contribution of discrete sources of radiation. Strategies for removing these ambiguities are discussed.

scholarly journals The Angular Distribution of the Cosmic Background Radiation

1986 ◽  
Vol 7 ◽  
pp. 307-319
Author(s):  
R. B. Partridge
Keyword(s):  
Angular Distribution ◽  
Early Universe ◽  
Background Radiation ◽  
Cosmic Background Radiation ◽  
Current Status ◽  
Microwave Background ◽  
Cosmic Background ◽  
Dipole Component ◽  
Upper Limits ◽  
Microwave Background Radiation

AbstractCrucial cosmological information is provided by the observed angular distribution (isotropy) of the cosmic microwave background radiation. This report treats the current status of searches for anisotroples in this radiation on all angular scales from 180° (the dipole component) to 6″. With the exception of the dipole component, only upper limits (at ~ 10-4 in ΔT/T) are available, yet these upper limits have played an important role in refining models of the early Universe and of the origin of structure within it.

scholarly journals New Limits to the Small Scale Fluctuations in the Cosmic Background Radiation

1983 ◽  
Vol 104 ◽  
pp. 125-126
Author(s):  
K. I. Kellermann ◽  
E. B. Fomalont ◽  
J. V. Wall
Keyword(s):  
Cosmic Microwave Background ◽  
Radio Source ◽  
Flux Density ◽  
Background Radiation ◽  
Cosmic Background Radiation ◽  
Small Region ◽  
Small Scale ◽  
Microwave Background ◽  
Cosmic Background ◽  
Microwave Background Radiation

The VLA has been used at 4.9 GHz to observe a small region of sky in order to extend the radio source count to low flux density (Fomalont et al., these proceedings) and to look for small scale fluctuations in the 2.7 K cosmic microwave background radiation.

A NEW VIEW ON THE PROBLEM OF ANISOTROPY OF THE COSMIC BACKGROUND RADIATION

1993 ◽  
Vol 02 (01) ◽  
pp. 97-104 ◽  
Author(s):  
V.G. GURZADYAN ◽  
A.A. KOCHARYAN
Keyword(s):  
Negative Curvature ◽  
Background Radiation ◽  
Cosmological Parameters ◽  
Cosmic Background Radiation ◽  
Geometrical Shape ◽  
Microwave Background ◽  
Cosmic Background ◽  
Microwave Background Radiation ◽  
History Of ◽  
The Universe

The anisotropy properties of the Cosmic Microwave Background Radiation (CMB) are considered within the framework of the photon beam mixing effect developed earlier. The existence of an observable characteristic of the CMB is shown, namely the geometrical shape of anisotropy spots and their degree of complexity, which can contain unique information on cosmological parameters and the life history of the Universe. If future experiments (COBE and others) indicate such features of anisotropy maps, then one can have serious evidence for the negative curvature of the Universe.

scholarly journals 4. Galaxy formation

1985 ◽  
Vol 19 (1) ◽  
pp. 668-677
Author(s):  
Bernard J. T. Jones
Keyword(s):  
Galaxy Formation ◽  
Large Scale ◽  
Background Radiation ◽  
Mass Density ◽  
Cosmic Background Radiation ◽  
Cosmic Background ◽  
Scant Attention ◽  
The Subject ◽  
The Universe

This article surveys the literature from July 1981 to June 1984. It is neither possible nor desirable to refer to all papers on the subject, and accordingly only papers that are generally representative of some particular idea are explicitly mentioned. Galaxy Formation by its very nature has considerable overlap with other areas of cosmology such as the anisotropy of the cosmic background radiation, the question of the mass density of the universe, the nature of the large scale clustering, and detailed observations of galaxies. These are all topics covered by other reports to Commission 47 and the reader will therefore find only scant attention paid here to these important subjects.

On the cosmic background radiation and the age of the Universe

2013 ◽  
Vol 26 (3) ◽  
pp. 358-361
Author(s):  
Leandro Meléndez Lugo
Keyword(s):  
Background Radiation ◽  
Cosmic Background Radiation ◽  
Big Bang ◽  
Microwave Background ◽  
Dispersion Process ◽  
Cosmic Background ◽  
Microwave Background Radiation ◽  
Age Of The Universe ◽  
The Big Bang ◽  
The Universe

A basic fundamental analysis indicates that any radiation emitted by remote objects, such as galaxies and quasars, has only a limited age in comparison with that of the Universe. The radiation emitted by such objects thousands of millions of years ago is the oldest one that can be detected. Any previous radiation emitted by these bodies during their dispersion process resulting from the Universe expansion cannot be detected. It is shown on the basis of this analysis that the age of the Universe is much greater than that established as 13,700 millions of years and that the cosmic microwave background radiation must have a source other than the Big Bang.

Statistics of Cosmic Microwave Background Radiation with the Cosmic String Model

1997 ◽  
Vol 06 (05) ◽  
pp. 535-544
Author(s):  
Petri Mähönen ◽  
Tetsuya Hara ◽  
Toivo Voll ◽  
Shigeru Miyoshi
Keyword(s):  
Cosmic Microwave Background ◽  
Cosmic String ◽  
Large Scale ◽  
Background Radiation ◽  
Unit Length ◽  
Angular Size ◽  
Cosmic Microwave Background Radiation ◽  
Density Parameter ◽  
Microwave Background ◽  
Microwave Background Radiation

We have studied the cosmic microwave background radiation by simulating the cosmic string network induced anisotropies on the sky. The large-angular size simulations are based on the Kaiser–Stebbins effect calculated from full cosmic-string network simulation. The small-angular size simulations are done by Monte-Carlo simulation of perturbations from a time-discretized toy model. We use these results to find the normalization of μ, the string mass per unit length, and compare this result with one needed for large-scale structure formation. We show that the cosmic string scenario is in good agreement with COBE, SK94, and MSAM94 microwave background radiation experiments with reasonable string network parameters. The predicted rms-temperature fluctuations for SK94 and MSAM94 experiments are Δ T/T=1.57×10-5 and Δ T/T=1.62×10-5, respectively, when the string mass density parameter is chosen to be Gμ=1.4×10-6. The possibility of detecting non-Gaussian signals using the present day experiments is also discussed.

The TopHat Cosmic Microwave Background Anisotropy Experiment

2005 ◽  
Vol 201 ◽  
pp. 65-70
Author(s):  
Robert F. Silverberg ◽  
Keyword(s):  
Cosmic Microwave Background ◽  
Large Scale ◽  
Background Radiation ◽  
High Sensitivity ◽  
Microwave Background ◽  
Long Duration ◽  
Cosmic Microwave Background Anisotropy ◽  
Microwave Background Radiation ◽  
The Universe ◽  
Large Scale Structure Formation

We have developed a balloon-borne experiment to measure the Cosmic Microwave Background Radiation anisotropy on angular scales from ˜50° down to ˜20′. The instrument observes at frequencies between 150 and 690 GHz and will be flown on an Antarctic circumpolar long duration flight. To greatly improve the experiment performance, the front-end of the experiment is mounted on the top of the balloon. With high sensitivity, broad sky coverage, and well-characterized systematic errors, the results of this experiment can be used to strongly constrain cosmological models and probe the early stages of large-scale structure formation in the Universe.

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