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Evolution of Scale-invariant Inhomogeneities in Standard Cosmology

Elcio Abdalla·Roya Mohayaee
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Abstract

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 contrary, the rapid growth of the density instabilities makes an open universe inhomogeneous in a time scale comparable to the age of our universe. We also find that the fluctuations grow exponentially in a flat inflationary universe.

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Elcio Abdalla, Roya Mohayaee. 1997-11-14. Evolution of Scale-invariant Inhomogeneities in Standard Cosmology. https://arxiv.org/abs/astro-ph/9711162

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