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arXiv · 2206.14300

Dark Energy from the Fifth Dimension

A. Stern·Chuang Xu
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Abstract

After extending the Regge-Teitelboim formulation of gravity to include the case where the background embedding space is not flat, we examine the dynamics of the four-dimensional $k=0$ Robertson-Walker (RW) manifold embedded in various five-dimensional backgrounds. We find that when the background is five-dimensional de Sitter space, the RW manifold undergoes a transition from a de-accelerating phase to an accelerating phase. This occurs before the inclusion of matter, radiation or cosmological constant sources, and thus does not require a balance of different components. We obtain a reasonable two-parameter fit of this model to the Hubble parameter data.

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A. Stern, Chuang Xu. 2022-06-28. Dark Energy from the Fifth Dimension. https://doi.org/10.1103/physrevd.107.024001

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