Perturbations and the future conformal boundary

The concordance model of cosmology predicts a universe which finishes in a finite amount of conformal time at a future conformal boundary. We show that for particular cases we study, the background variables and perturbations may be analytically continued beyond this boundary and that the ???end of the universe??? is not necessarily the end of their physical development. Remarkably, these theoretical considerations of the end of the universe might have observable consequences today: perturbation modes consistent with these boundary conditions have a quantized power spectrum which may be relevant to features seen in the large scale cosmic microwave background. Mathematically these cosmological models may either be interpreted as a palindromic universe mirrored in time, a reflecting boundary condition, or a double cover, but are identical with respect to their observational predictions and stand in contrast to the predictions of conformal cyclic cosmologies.

Automated summary

The concordance model of cosmology predicts the end of the universe at a future conformal boundary, but for specific cases, the background variables and perturbations can be continued beyond this boundary. These theoretical considerations might have observable consequences today and can be relevant to the power spectrum of perturbation modes in the cosmic microwave background.