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arXiv · 1106.5743

Five-dimensional warped product space-time with time-dependent warp factor and cosmology of the four-dimensional universe

Sarbari Guha·Subenoy Chakraborty
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Abstract

In this paper, we have studied a 5-dimensional warped product space-time with a time-dependent warp factor. This warp factor plays an important role in localizing matter to the 4-dimensional hypersurface constituting the observed universe and leads to a geometric interpretation of dynamical dark energy. The five-dimensional field equations are constructed and its solutions are obtained. The nature of modifications produced by this warp factor in the bulk geometry is discussed. The hypersurface is described by a flat FRW-type metric in the ordinary spatial dimension. It is found that the effective cosmological constant of the four-dimensional universe is a variable quantity monitored by the time-dependent warp factor. The universe is initially decelerated, but subsequently makes a transition to an accelerated phase at later times.

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Sarbari Guha, Subenoy Chakraborty. 2011-06-28. Five-dimensional warped product space-time with time-dependent warp factor and cosmology of the four-dimensional universe. https://doi.org/10.1007/s10773-011-0877-9

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