2007/07/10 by S. K. Srivastava, Srivastava, S. K.
Physics and Astronomy · #Cosmology and Gravitation Theories #FOS: Physical sciences #Galaxies: Formation, Evolution, Phenomena #General Relativity and Quantum Cosmology (gr-qc) #Solar and Space Plasma Dynamics #gr-qc
paper · pdf · doi:10.48550/arxiv.0707.1376
17 pages
openalex publication_date 2007/07/10 · arxiv created 2008/01/02 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
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 is negative) drastically. 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= 2 λ. 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 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.