Rescuing Palindromic Universes with Improved Recombination Modelling

Abstract

We explore the linearly quantised primordial power spectra associated with palindromic universes. Extending the results of Lasenby et al. [1] and Bartlett et al. [2], we improve the modelling of recombination and include higher orders in the photonic Boltzmann hierarchy. In so doing, we find that the predicted power spectra become largely consistent with observational data. The improved recombination modelling involves developing further techniques for dealing with the future conformal boundary, by integrating the associated perturbation equations both forwards and backwards in conformal time. The resulting wavevector quantisation gives a lowest allowed wavenumber $k_0=9.93\times 10^{-5}{\text{Mpc}}^{-1}$ and linear spacing $\Delta k=1.63\times 10^{-4}{\text{Mpc}}^{-1}$, providing fits consistent with observational data equivalent in quality to the $\Lambda$CDM model.

Submitted in PRD

References in corpus (6)

• Planck CMB Anomalies: Astrophysical and Cosmological Secondary Effects and the Curse of Masking
• Constraining Quantum Initial Conditions before Inflation
• Two-Sheeted Universe, Analyticity and the Arrow of Time
• Cosmological perturbations without the Boltzmann hierarchy
• Improved cosmological fits with quantized primordial power spectra
• Perturbations and the Future Conformal Boundary