Amplitude of primeval fluctuations from cosmological mass density reconstructions
نویسندگان
چکیده
منابع مشابه
Amplitude of Primeval Fluctuations from Cosmological Mass Density Reconstructions
We use the POTENT reconstruction of the mass density field in the nearby universe to estimate the amplitude of the density fluctuation power spectrum for various cosmological models. We find σ8 Ω 0.6 m = 1.3 +0.4 −0.3, almost independently of the power spectrum. This value agrees well with the COBE normalization for the standard CDM model, while some alternative models predict an excessive ampl...
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The amplitude of cosmological density fluctuations, σ8, has been studied and estimated by analysing many cosmological observations. The values of the estimates vary considerably between the various probes. However, different estimators probe the value of σ8 in different cosmological scales and do not take into account the nonlinear evolution of the parameter at late times. We relate the linear ...
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ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 1994
ISSN: 0004-637X,1538-4357
DOI: 10.1086/174163