Spherical collapse model with non-clustering dark energy
نویسنده
چکیده
We investigate a spherical overdensity model for the non-clustering dark energy (DE) with the constant equation of state, ωde in a flat universe. In this case, the exact solution for the evolution of the scale factor is obtained for general ωde. We also obtain the exact (when ωde = −13) and the approximate (when ωde 6= −13) solutions for the ratio of the overdensity radius to its value at the turnaround epoch (y ≡ R Rta ) for general cosmological parameters. Also the exact and approximate solutions of the overdensity at the turnaround epoch ζ = ρcluster ρm ∣
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