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arXiv · 1810.05540

Curvature Late-Time Acceleration in an Eternal Universe

Rodrigo Maier·Ivano Damião Soares
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Abstract

We construct a FLRW universe considering an anisotropic scaling between space and time at extremely high and low energies only. In this context, Friedmann equations contain an additional term arising from spatial curvature which implements nonsingular bounces in the early Universe. The matter content of the model is a nonrelativistic pressureless perfect fluid and radiation. By breaking covariance diffeomorphism also at extreme large scales, an additional term furnishes late-time acceleration due to spatial curvature so that a cosmological constant is not needed. In order to probe the final fate of the universe we also introduce a lower order curvature term which dominates in deep IR. Given the observational parameters we obtain a concrete model in eternal recurrence in which the end of late-time acceleration takes place at a redshift $z \simeq -0.14$ and the universe recollapses at $z\simeq - 0.32$.

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Rodrigo Maier, Ivano Damião Soares. 2018-10-11. Curvature Late-Time Acceleration in an Eternal Universe. https://doi.org/10.1088/1475-7516%2F2018%2F12%2F029

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