Puzzling initial conditions in the $$R_\mathrm{h}=ct$$ R h = c t model

Abstract

In recent years, some studies have drawn attention to the lack of large-angle correlations in the observed cosmic microwave background (CMB) temperature anisotropies with respect to that predicted within the standard CDM model. Lately, it has been argued that such a lack of correlations could be explained in the framework of the so-called R h = ct model without inflation. The aim of this work is to study whether there is a mechanism to generate, through a quantum field theory, the primordial power spectrum presented by these authors. Specifically, we consider two different scenarios: first, we assume a scalar field dominating the early Universe in the R h = ct cosmological model, and second, we deal with the possibility of adding an early inflationary phase to the mentioned model. During the analysis of the consistency between the predicted and observed amplitudes of the CMB temperature anisotropies in both scenarios, we run into deep issues which indicate that it is not clear how to characterize the primordial quantum perturbations within the R h = ct model.

Plasma Perturbations and Cosmic Microwave Background Anisotropy in the Linearly Expanding Milne-Like Universe

“…expressed through a dimensionless quantity Ω b , a proton mass m p and a critical density M 2 p H 2 /2. Formally, for the dependence given by (12), an integration in (31) has to begin from η = −∞. However, as was shown in [28], the universe started from a power-law expansion changed by (12) afterward.…”

“…physical) time t in corresponding to the conformal time η in . Integrating with (12) gives t in = η in 0 a(η)dη ≈ B η in , where it is taken into account that H η in ≪ 1. For instance, taking η in = 0.06/H and B = 3.8 × 10 −38 gives t in = 5.9 × 10 −22 s, which corresponds to the lifetime of the Higgs boson t H = 2π/Γ H , where Γ H = 7 MeV .…”

“…Recently, the Milne-like cosmologies considering the linearly expanding (in cosmic time) universe models [4,5] again attract an attention [6][7][8][9][10][11][12][13][14][15]. Instead of the 1 z is the red-shift parameter used as a measure of cosmological time and distance: z+ 1 = a 0 /a(η), where a 0 is the present scale factor value, and a(η) is the scale factor at some earlier photon emission time τ [1, 2].…”

“…Recently, the Milne-like cosmologies considering the linearly expanding (in cosmic time) universe models [4,5] again attract an attention [6][7][8][9][10][11][12][13][14][15]. Instead of the…”

“…Protons and electrons were coupled to the radiation through the Compton scattering by electrons which in turn are coupled to the baryons by Coulomb interaction [1,3]. Such primordial plasma perturbations were widely considered in cosmology, and their fingerprints depend on a law of the universe expansion that is the crucial point for our further analysis.Recently, the Milne-like cosmologies considering the linearly expanding (in cosmic time) universe models [4,5] again attract an attention [6][7][8][9][10][11][12][13][14][15]. Instead of the 1 z is the red-shift parameter used as a measure of cosmological time and distance: z+ 1 = a 0 /a(η), where a 0 is the present scale factor value, and a(η) is the scale factor at some earlier photon emission time τ [1, 2].…”