Equation-of-state formalism for dark energy models on the brane and the future of brane universes

Abstract

Brane dark energy cosmologies, leading to various possible evolutions of our universe, are investigated. The discussion shows that while all these models can be made arbitrarily close to the standard ΛCDM cosmology at present, their future evolutions can be very different, even diverge with time in a number of ways. This includes asymptotic de-Sitter evolution, Little Rip with dissolution of bound structures, and various possible singularities, as the Big Rip, a sudden future singularity (Type II), and Type III and Type IV cases. Specifically, some interesting effects coming from the brane tension are investigated. It is shown, in particular, that the Little Rip occurs faster on the brane model than in usual FRW cosmology. And in the asymptotic de-Sitter regime the influence of the brane tension leads to a deviation of the value of the effective cosmological constant from that corresponding to ordinary dark energy. As a consequence, the value of the inertial force from the accelerating expansion can greatly exceed the corresponding inertial force in ordinary cosmological models.

Little Rip and Pseudo Rip Phenomena From Coupled Dark Energy

“…Second example. This example considers a cosmological model with asymptotically de Sitter evolution [20]. The Hubble parameter is taken equal to [25] H…”

“…Very general dark fluid models with an inhomogeneous EoS were introduced in [8,9,10,11]. There exist various cosmological scenarios for the evolution of the universe including the Big Rip [12,13,14], the Little Rip [15,16,17,18,19,20,21,22], the Pseudo Rip [23] and the Quasi Rip [24].…”

Brane cosmology from observational surveys and its comparison with standard FRW cosmology

“…The EoS formalism for dark energy models on the brane was considered in [32]. Here we briefly describe this approach.…”

Viscous accelerating universe with nonlinear and logarithmic equation of state fluid

“…There are various scenarious for the evolution of the accelerating universe. Notably, the final stage may be in the form of a Big Rip [5][6][7], a Little Rip [8][9][10][11][12][13][14], a Pseudo Rip [15], a Quasi Rip [16], or a bounce cosmology [17,18].…”