Assume a flat Friedmann-Robertson-Walker universe, and that the density parameters for matter, radiation, and the cosmological constant are given today by Ωm,0 = 0.4, Ωrad,0 = 0.01, and ΩΛ,0 = 0.59, respectively. a) Calculate the redshifts for matter-radiation and matter-dark energy equality. b) State what effect the lower ratio of ΩΛ,0/Ωm,0, compared to the standard Λ-CDM cosmology, has on structure formation.

Assume a flat Friedmann-Robertson-Walker universe, and that the density parameters for matter, radiation, and the cosmological constant are given today by Ωm,0 = 0.4, Ωrad,0 = 0.01, and ΩΛ,0 = 0.59, respectively. a) Calculate the redshifts for matter-radiation and matter-dark energy equality. b) State what effect the lower ratio of ΩΛ,0/Ωm,0, compared to the standard Λ-CDM cosmology, has on structure formation.

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Question

Assume a flat Friedmann-Robertson-Walker universe, and that the density parameters for matter,
radiation, and the cosmological constant are given today by Ωm,0 = 0.4, Ωrad,0 = 0.01, and ΩΛ,0 =
0.59, respectively.
a) Calculate the redshifts for matter-radiation and matter-dark energy equality.

b) State what effect the lower ratio of ΩΛ,0/Ωm,0, compared to the standard Λ-CDM cosmology,
has on structure formation.

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