New futures for cosmological models

Abstract

The discovery of accelerated expansion of the Universe opened up the possibility of new scenarios for the doom of our space–time, besides eternal expansion and a final contraction. In this paper, we review the chances that may await our universe. In particular, there are new possible singular fates (sudden singularities, big rip, etc.), but there also other evolutions that cannot be considered as singular. In addition to this, some of the singular fates are not strong enough in the sense that the space–time can be extended beyond the singularity. For deriving our results, we make use of generalized power and asymptotic expansions of the scale factor of the Universe. This article is part of the theme issue ‘The future of mathematical cosmology, Volume 1’.

Recent Advances in Cosmological Singularities

“…There has been substantial work on new dark energy models based on thermodynamic modifications like modified area-entropy relations [151][152][153][154][155][156], even more exotic possibilities like generalized uncertainty principles [157][158][159], or non-canonical approaches like DBI [160][161][162][163][164][165][166]. This vast dark energy literature has prompted the study of cosmological singularities with a wide range of cosmological backgrounds, as there have been multiple works that have discussed Type I-IV singularities in various cosmologies [29,30,32,33,93,143,[167][168][169][170][171][172][173][174][175][176][177][178]. In this vast array of literature, one can find quite a few examples where cosmologies affected by these modified gravity theories or quantum gravitational paradigms (like the braneworld or LQC) have alleviated certain singularities.…”

Phantom attractors in kinetic gravity braiding theories: a dynamical system approach

“…Moreover, this finitescale-factor singularity could take place at a finite cosmic time. (See references [39][40][41][42] for other examples of cosmological singularities.) Therefore, since the future phenomenology of (phantom) DE models could encompass a broad variety of possibilities, it is natural to wonder whether the (phantom) DE component modelled by the shift-symmetric KGB theories could lead the evolution of the cosmos towards a different future state from that of the well-studied dS future solution of the theory.…”

Determinants of Financial Inclusion of Urban Women: Evidence from Ahmedabad, India

“…There has been substantial work on new dark energy models based on thermodynamic modifications like modified area-entropy relations [163][164][165][166][167][168] or even more exotic possibilities like generalized uncertainty principles [169][170][171] or non-canonical approaches like DBI etc. as well [172][173][174][175][176][177][178].This vast dark energy literature has prompted the study of cosmological singularities in a wide range of cosmological backgrounds as well, as there have been multiple works which have discussed Type I-IV singularities in various cosmologies [30,31,33,34,105,155,[179][180][181][182][183][184][185][186][187][188][189][190]. In this vast array of works, one has seen quite a few examples in which cosmologies affected by the effects of these modified gravity theories or quantum gravitational paradigms ( like the Braneworld or LQC for example ) have alleviated certain singularities.…”