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arXiv · 2104.06107

Unified Dark Energy and Dark Matter from Dynamical Spacetime Cosmology

David Benisty
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Abstract

A model of unified dark matter and dark energy based on a Dynamical Spacetime Theory (DST) is studied. By introducing a Dynamical Spacetime vector field $χ_μ$, a conservation of an energy momentum tensor $T^{μν}_{(χ)}$ emerges. The action allows for two different potentials, while one represents a dark energy. For constant potentials, the cosmological solution yields a non singular bouncing solutions that rapidly approaches the $Λ$CDM model. The Dynamical Time corresponds to the cosmic time as well. The theory fits with the late time expansion data of the Universe. With higher dimensions a mechanism for inflation and compactification appears, with exponential growth for some dimensions and exponential contraction of the others. By demanding that the Dynamical Spacetime vector field be a gradient of a scalar the DST becomes a theory with diffusive interacting, which asymptotically returns to the $Λ$CDM model as a stable point. These formulations lead to scenarios which address our understanding about the origin of the Universe.

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David Benisty. 2021-04-13. Unified Dark Energy and Dark Matter from Dynamical Spacetime Cosmology. https://doi.org/10.1142/9789811258251_0037

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