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  • 1
    Electronic Resource
    Electronic Resource
    Distortions of the Background Radiation Spectrum (1969)
    [s.l.] : Nature Publishing Group
    Nature 223 (1969), S. 721-722 
    Details
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] But if departures from the equilibrium spectrum were discovered, what would their meaning be ? We believe that one need not abandon the hot, big-bang theory. There are natural processes which can lead to pronounced distortions of the spectrum, both in the low-frequency (Rayleigh-Jeans) and ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/223721a0
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  • 2
    Electronic Resource
    Electronic Resource
    COSMOLOGICAL IMPACT OF THE NEUTRINO REST MASS (1981)
    Oxford, UK : Blackwell Publishing Ltd
    Annals of the New York Academy of Sciences 375 (1981), S. 0 
    Details
    ISSN: 1749-6632
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Natural Sciences in General
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1749-6632.1981.tb33688.x
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  • 3
    Electronic Resource
    Electronic Resource
    The interaction of matter and radiation in the hot model of the Universe, II (1970)
    Springer
    Astrophysics and space science 7 (1970), S. 20-30 
    Details
    ISSN: 1572-946X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract Heating of the primaeval plasma prior to the epoch of recombination results in distortions in the Rayleigh-Jeans region of the microwave relic radiation spectrum (λ∼1–60 cm, or more exactly λ=2.5Ω−7/8 cm). The present observational data allow limits to be set to such energy injection from which follow upper limits to (a) the amount of antimatter in the universe; (b) the parameters of primaeval turbulence; and (c) the adiabatic fluctuation spectrum for small masses (M〈1011 M ⊙). If the heating takes place prior to the epocht=1010Ω12/5 sec (and in particular at the annihilation of electron-positron pairs atT∼108–1010 K,t〈300 sec), no observable distortions are expected in the relic radiation spectrum. Here Ω=ϱ/ϱcrit is the dimensionless average density of matter in the universe.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00653472
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  • 4
    Electronic Resource
    Electronic Resource
    The interaction of matter and radiation in a hot-model universe (1969)
    Springer
    Astrophysics and space science 4 (1969), S. 301-316 
    Details
    ISSN: 1572-946X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract In this paper we continue the investigation initiated by Weymann as to the reason why the spectrum of the residual radiation deviates from a Planck curve. We shall consider the distortions of the spectrum resulting from radiation during the recombination of a primeval plasma. Analytical expressions are obtained for the deviation from an equilibrium spectrum due to Compton scattering by hot electrons. On the basis of the observational data it is concluded that a period of neutral hydrogen in the evolution of the universe is unavoidable. It is shown that any injection of energy att〉1010 sec (red shiftz〈105) leads to deviation from an equilibrium spectrum.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00661821
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  • 5
    Electronic Resource
    Electronic Resource
    Small-scale fluctuations of relic radiation (1970)
    Springer
    Astrophysics and space science 7 (1970), S. 3-19 
    Details
    ISSN: 1572-946X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract Perturbations of the matter density in a homogeneous and isotropic cosmological model which leads to the formation of galaxies should, at later stages of evolution, cause spatial fluctuations of relic radiation. Silk assumed that an adiabatic connection existed between the density perturbations at the moment of recombination of the initial plasma and fluctuations of the observed temperature of radiation δT/T=δ ϱm /3 ϱm . It is shown in this article that such a simple connection is not applicable due to: (1) The long time of recombination; (2) The fact that when regions withM〈1015 M ⊙ become transparent for radiation, the optical depth to the observer is still large due to Thompson scattering; (3) The spasmodic increase of δ ϱm/ϱm in recombination. As a result the expected temperature fluctuations of relic radiation should be smaller than adiabatic fluctuations. In this article the value of δT/T arising from scattering of radiation on moving electrons is calculated; the velocity field is generated by adiabatic or entropy density perturbations. Fluctuations of the relic radiation due to secondary heating of the intergalactic gas are also estimated. A detailed investigation of the spectrum of fluctuations may, in principle, lead to an understanding of the nature of initial density perturbations since a distinct periodic dependence of the spectral density of perturbations on wavelength (mass) is peculiar to adiabatic perturbations. Practical observations are quite difficult due to the smallness of the effects and the presence of fluctuations connected with discrete sources of radio emission.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00653471
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  • 6
    Electronic Resource
    Electronic Resource
    Giant voids in the Universe (1982)
    [s.l.] : Nature Publishing Group
    Nature 300 (1982), S. 407-413 
    Details
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Recent observations indicate that most galaxies are concentrated in superclusters consisting of galaxies, and clusters of galaxies, aligned along strings. Giant volumes exist between superclusters which are almost empty of visible objects. Theories of galaxy formation predict the formation of ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/300407a0
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  • 7
    Electronic Resource
    Electronic Resource
    Making waves on Shelter Island (1986)
    [s.l.] : Nature Publishing Group
    Nature 324 (1986), S. 194-194 
    Details
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Shelter Island II. Proceedings of the 1983 Shelter Island Conference on Quantum Field Theory and the Fundamental Problems of Physics. Edited by Roman Jackiw, Nicola N. Khuri, Steven Weinberg and Edward Witten. MIT Press: 2985. Pp. 369. 37.50, Â37.50. THE proceedings contained in this book are best ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/324194a0
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  • 8
    Electronic Resource
    Electronic Resource
    Small scale entropy and adiabatic density perturbations — Antimatter in the Universe (1970)
    Springer
    Astrophysics and space science 9 (1970), S. 368-382 
    Details
    ISSN: 1572-946X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract Fluctuations of all scales are equally interesting from the point of view of the characteristics of the singular state and not only those which led to the formation of astronomical objects such as clusters of galaxies, separate galaxies, globular clusters and quasars. In this article estimates are given of the homogeneity of the overall density of hot plasma and the relation between the quantity of baryons and antibaryons at early stages of evolution of the Universe. These estimates are made for small scales, considerably smaller than the scale of the astronomical objects enumerated above. Considerations about the energy balance of hot plasma and distortions of the spectrum of relic radiation due to dissipation of density fluctuations of matter are used for these estimates. The corrected upper limit to early energy injection is given. In our preceding paper (Sunyaev and Zeldovich, 1970) this upper limit was underestimated. Difficulties with a model of the Universe which is symmetric in baryon charge are noted.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00649577
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  • 9
    Electronic Resource
    Electronic Resource
    On the electromagnetic detection of gravitational waves (1979)
    Springer
    General relativity and gravitation 11 (1979), S. 407-409 
    Details
    ISSN: 1572-9532
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract The general principles of the electromagnetic detection of gravitational waves are discussed. A critical comment on a previous paper by Baierlein [1] devoted to the same problem is given.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00759303
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