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arXiv · 1811.03660

Late-time Cosmic Acceleration from Compactification

J. G. Russo·P. K. Townsend
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Abstract

We investigate the implications of energy conditions on cosmological compactification solutions of the higher-dimensional Einstein field equations. It is known that the Strong Energy Condition forbids time-independent compactifications to de Sitter space but allows time-dependent compactifications to other (homogeneous and isotropic) expanding universes that undergo a {\it transient} period of acceleration. Here we show that the same assumptions allow compactification to FLRW universes undergoing {late-time} accelerated expansion; the late-time stress tensor is a perfect fluid but with a lower bound on the pressure/energy-density ratio that excludes de Sitter but allows accelerated power-law expansion. The compact space undergoes a decelerating expansion that leads to decompactification, but on an arbitrarily long timescale.

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J. G. Russo, P. K. Townsend. 2019-03-08. Late-time Cosmic Acceleration from Compactification. https://doi.org/10.1088/1361-6382%2Fab0804

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