منابع مشابه
Evolution of Scale-invariant Inhomogeneities in Standard Cosmology
It is shown that density fluctuations obey a scaling law in an open Friedmann universe. In a flat universe, the fluctuations are not scale-invariant. We compute the growth rate of adiabatic scale-invariant density fluctuations in flat, open and inflationary universes. We find that, given a sufficiently long time, the density perturbations decay away in the Einstein-de-Sitter universe. On the co...
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The large-scale structure of the Universe suggests that the physics underlying its early evolution is scalefree. This was the historic motivation for the Harrison-Zel’dovich-Peebles spectrum and for inflation. Based on a hydrodynamical approach, we identify scale-free forms for the background equation of state for both inflationary and cyclic scenarios and use these forms to derive predictions ...
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ژورنال
عنوان ژورنال: International Journal of Modern Physics D
سال: 1999
ISSN: 0218-2718,1793-6594
DOI: 10.1142/s0218271899000213