English

Can Phantom-Dominated Universe Decelerate Also in Future ?

General Relativity and Quantum Cosmology 2008-01-02 v6

Abstract

Here Randall-Sundrum brane-gravity models of the homogeneous and flat universe, dominated by phantom fluid, is considered. It is noted that brane-gravity corrections effect the behaviour of phantom fluid in RS-II model (where brane-tension λ\lambda is negative) drastically. It is interesting to see that, phantom fluid violates the weak energy condition (WEC) till energy density ρ<λ\rho < \lambda, but when phantom energy density ρ\rho grows more, the effective equation of state does not violate WEC. Moreover, with increasing phantom energy density, a stage comes when even strong energy condition is not violated due to effect of these corrections. Also expansion stops, when ρ=2λ\rho = 2 \lambda. As a consequence, RS-II phantom universe accelerates upto a finite time explaining the present cosmic acceleration, but it decelerates later.Thus, RS-II phantom universe is singularity-free. In the case of RS-I model, where λ\lambda is positive, characteristics of phantom fluid is not suppressed by brane-corrections and phantom universe accelerates ending up in big-rip singularity in finite future time.

Keywords

Cite

@article{arxiv.0707.1376,
  title  = {Can Phantom-Dominated Universe Decelerate Also in Future ?},
  author = {S. K. Srivastava},
  journal= {arXiv preprint arXiv:0707.1376},
  year   = {2008}
}

Comments

17 pages

R2 v1 2026-06-21T08:56:41.504Z