Improved cosmological fits with quantized primordial power spectra

Abstract

We observationally examine cosmological models based on primordial power spectra with quantized wave vectors. Introducing a linearly quantized power spectrum with k 0 ¼ 3.225 × 10 −4 Mpc −1 and spacing Δk ¼ 2.257 × 10 −4 Mpc −1 provides a better fit to the Planck 2018 observations than the concordance baseline, with Δχ 2 ¼ −8.55. Extending the results of Lasenby et al. [preceding paper, Perturbations and the future conformal boundary, Phys. Rev. D 105, 083514 ( 2022)], we show that the requirement for perturbations to remain finite beyond the future conformal boundary in a universe containing dark matter and a cosmological constant results in a linearly quantized primordial power spectrum. It is found that the infrared cutoffs for this future conformal boundary quantized cosmology do not provide cosmic microwave background power spectra compatible with observations, but future theories may predict more observationally consistent quantized spectra.

Perturbations and the future conformal boundary

“…This can then be compared against modern observational data from the cosmic microwave background [2] or supernovae [31]. An analysis in this regard can be found in our follow-up paper [15]. Given such a profound modification to the underlying cosmology, cosmologies such as these may have implications for the tensions between measurements of cosmological parameters at early and late times, such as those discussed in Ref.…”

“…In Figs. [13][14][15] we show the evolution of the perturbed quantities for the case K ¼ 10 where the integration starts from the values reached for these quantities at η ¼ 1 (chosen just for illustrative purposes). It is then continued through the future conformal boundary using the series expansions we will derive below, and then allowed to carry on its evolution numerically in the region beyond the FCB.…”

“…Finally, we discuss the CDM perturbations, and their analytic properties. A joint analysis of cold dark matter and radiation perturbations, and the effect of the FCB in this case, will be presented in a parallel paper [15], which will also consider some observational consequences which would follow if some of the ideas presented here were taken as applying to the actual Universe.…”