Sudden Future Singularity models as an alternative to dark energy?

Abstract

Current observational evidence does not yet exclude the possibility that dark energy could be in the form of phantom energy. A universe consisting of a phantom constituent will be driven towards a drastic end known as the ‘Big Rip’ singularity where all the matter in the universe will be destroyed. Motivated by this possibility, other evolutionary scenarios have been explored by Barrow, including the phenomena which he called Sudden Future Singularities (SFSs). In such a model it is possible to have a blow up of the pressure occurring at sometime in the future evolution of the universe while the energy density would remain unaffected. The particular evolution of the scale factor of the universe in this model that results in a singular behaviour of the pressure also admits acceleration in the current era. In this paper we will present the results of our confrontation of one example class of SFS models with the available cosmological data from high‐redshift SNe, baryon acoustic oscillations (BAOs) and the cosmic microwave background (CMB). We then discuss the viability of the model in question as an alternative to dark energy.

Redshift drift test of exotic singularity universes

“…[19], SFS2 is just the standard dust (Einstein-de Sitter) limit δ → 0 of the SFS models, and SFS3 is plotted for the observationally best-fit region (supernovae, BAO, shift parameter) of the parameters as given in Refs. [20,21] and gives a complementary test of SFS models. As can be seen from the plots, SFS3 can mimic ΛCDM model, while SFS1 behaves differently than ΛCDM for large redshifts.…”

Fate of bound systems through sudden future singularities

“…[65,66] using standard ruler and standard candle cosmological data constraining the form of the past expansion history of the universe. The possible existence of such events in the future light cone has also been investigated under specific assumptions of the functional form of the future Hubble expansion rate [67][68][69][70][71][72][73].…”

Cosmological tests of sudden future singularities

“…Note that, as we discussed in [24], this value is not directly "observed" but is derived from the CMB data assuming a specific class of cosmological model; hence one must be careful in employing it to test our SFS model. However, as we showed in [24], the effective equation of state for our SFS model displays general similarity to that of the concordance model and on this basis we consider the use of the "observed" value of the shift parameter to be appropriate for our SFS model too.…”

“…In Ref. [24] we extended our investigation to confront SFS models with other cosmological data, from the cosmic microwave background (CMB) and baryon acoustic oscillations. We demonstrated that the class of SFS models introduced in [1] was not compatible with current observations, in the particular case where the asymptotic behaviour of the scale factor close to the BB singularity mimics a dustfilled Einstein de Sitter universe.…”