FLRW Universes from "Wave-Like" Cosmologies in 5D

Abstract

We consider the evolution of a 4D-universe embedded in a five-dimensional (bulk) world with a large extra dimension and a cosmological constant. The cosmology in 5D possesses "wave-like" character in the sense that the metric coefficients in the bulk are functions of the extra coordinate and time in a way similar to a pulse or traveling wave propagating along the fifth dimension. This assumption is motivated by some recent work presenting the big-bang as a higher dimensional shock wave. We show that this assumption, together with an equation of state for the effective matter quantities in 4D, allows Einstein's equations to be fully integrated. We then recover the familiar FLRW universes, on the four-dimensional hypersurfaces orthogonal to the extra dimension. Regarding the extra dimension we find that it is {\em growing} in size if the universe is speeding up its expansion. We also get an estimate for the relative change of the extra dimension over time. This estimate could have important observational implications, notably for the time variation of rest mass, electric charge and the gravitational "constant". Our results extend previous ones in the literature.

Few comments added, references updated. To appear in Int. J. of Mod. Phys. D

References in corpus (4)

• The Structure of the Big Bang from Higher-Dimensional Embeddings
• Mass and Charge in Brane-World and Non-Compact Kaluza-Klein Theories in 5 Dim
• Invariant definition of rest mass and dynamics of particles in 4D from bulk geodesics in brane-world and non-compact Kaluza-Klein theories
• Variation of G, ${\Lambda }_{(4)}$ and Vacuum Energy From Brane-World Models

Cited by in corpus (7)

• Brane-world models emerging from collisions of plane waves in 5D
• 4D spacetimes embedded in 5D light-like Kasner universes
• Wave-like Solutions for Bianchi type-I cosmologies in 5D
• The importance of scalar fields as extradimensional metric components in Kaluza-Klein models
• Self-similar cosmologies in 5D: spatially flat anisotropic models
• An exact self-similar solution for an expanding ball of radiation
• Cosmological solutions in the brane-bulk system