2006/04/30 by D. Panigrahi, Y. Z. Zhang, S. Chatterjee · 1 citation
Earth and Planetary Sciences · Physics and Astronomy · #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories #Geophysics and Gravity Measurements #gr-qc
paper · pdf · doi:10.1142/s0217751x06034318
published as Int.J.Mod.Phys. A21 (2006) 6491-6512 · 20 pages,3 figures
arxiv created 2006/09/12 · openalex publication_date 2006/12/20 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Homogeneous cosmological solutions are obtained in five-dimensional (5D) space–time assuming equations of state p = kρ and p 1 = γρ where p is the isotropic 3-pressure and p 1 , that for the fifth dimension. Using different values for the constants k and γ many known solutions are rediscovered. Further the current acceleration of the universe has led us to investigate higher dimensional gravity theory, which is able to explain acceleration from a theoretical viewpoint without the need of introducing dark energy by hand. We also extend a recent work of Mohammedi where using a special form of the extra dimensional scale factor a new interpretation of the higher dimensional equations of motion is given and the concept of an effective 4D pressure is introduced. Interestingly the 5D matter field remains regular while the effective negative pressure is responsible for the inflation. Relaxing the assumptions of two equations of state we also present a class of solutions which provide early deceleration followed by a late acceleration in a unified manner. Relevant to point out that in this case our cosmology apparently mimics the well-known quintessence scenario fuelled by a generalized Chaplygin-type of fluid where a smooth transition from a dust dominated model to a de Sitter-like one takes place. Depending on the relative magnitude of the different constants appearing in our solutions we show that some of the cases are amenable to the desirable property of dimensional reduction.