Late-time Cosmic Acceleration from Compactification.
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 (SEC) forbids time-independent compactifications to de Sitter space but allows time-dependent compactifications to other accelerating (homogeneous and isotropic) universes if the acceleration is transient. Here we show, by example, that late-time accelerated expansion is also compatible with the SEC (and with the Dominant Energy Condition). In these examples, the compact space is also expanding, suggesting that the ultimate fate of the Universe may be decompactification.
Publisher URL: http://arxiv.org/abs/1811.03660