Remark on the Theory of Cosmological Perturbation
نویسنده
چکیده
It is generally predicted that there exists non-vanishing power spectrum for the wavenumbers outside the Hubble radius in the inflationary scenario. The power spectrums differ dramatically for these wavenumbers in different gauges, so we must adopt a proper power spectrum to calculate the predictions of the cosmological model. In this paper I try to show that the power spectrum defined in the Synchronous Gauge can not be directly used to calculate the predictions of cosmological models on the large-scale structure of universe. These predictions should be calculated directly by the gauge-invariant power spectrum which characterizes the density fluctuation relative to the unperturbed expanding background of universe, or, by the power spectrum defined in the Newtonian Gauge. PACS: 98.80.-k; 98.80.Hw; 98.80.Cq
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