7 Can Phantom - Dominated Universe Decelerate Also in Future ?

Abstract

Here Randall-Sundrum models of the homogeneous and flat universe, dominated by phantom fluid, is considered. It is noted that branegravity corrections effect drastically on the behaviour of phantom fluid in RS-II model, where brane-tension λ is negative. It is interesting to see that, phantom fluid violates the weak energy condition (WEC) till energy density ρ < λ, but when phantom energy density ρ 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. As a cosequence, RS-II phantom universe accelerates upto a finite time explaining the present cosmic acceleration , but it decelerates later. In the case of RS-I model, where λ is positive, characterisics of phantom fluid is not suppressed by branecorrections and phantom universe accelerates ending up in big-rip singularity in finite future time. 1

Cite this paper

@inproceedings{Srivastava20087CP, title={7 Can Phantom - Dominated Universe Decelerate Also in Future ?}, author={Sanjeev K . Srivastava}, year={2008} }