Amplitude of Primeval Fluctuations from Cosmological Mass Density Reconstructions
نویسنده
چکیده
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 amplitude compared with COBE. Flat low Ωm models and tilted models with spectral index n < 0.8 are particularly discordant. Subject headings: cosmic microwave background — cosmology: large-scale structure of the universe
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تاریخ انتشار 1993