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arXiv · 2202.04323

A unified geometric description of the Universe: from inflation to late-time acceleration without an inflaton nor a cosmological constant

Luisa G. Jaime·Gustavo Arciniega
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Abstract

We present a cosmological model arising from a gravitational theory with an infinite tower of higher-order curvature invariants that can reproduce the entire evolution of the Universe: from inflation to late-time acceleration, without invoking an inflaton nor a cosmological constant. The theory is Einsteinian-like. The field equations for a Friedmann-Lemaître-Robertson-Walker metric are of second-order and can reproduce a late-time evolution that is consistent with the acceleration provided by the cosmological constant at low redshift. Our results force us to reinterpret the nature of dark energy, becoming a mechanism that is inherited solely from the geometry of spacetime.

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Luisa G. Jaime, Gustavo Arciniega. 2022-02-09. A unified geometric description of the Universe: from inflation to late-time acceleration without an inflaton nor a cosmological constant. https://doi.org/10.1016/j.physletb.2022.136939

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