A Unified Universe

Abstract

We present a unified evolution of the universe from very early times until the present epoch by including both the leading local correction $R^2$ and the leading non-local term $R\frac{1}{{\square }^2}R$ to the classical gravitational action. We find that the inflationary phase driven by $R^2$ term gracefully exits in a transitory regime characterized by coherent oscillations of the Hubble parameter. The universe then naturally enters into a radiation dominated epoch followed by a matter dominated era. At sufficiently late times after radiation-matter equality, the non-local term starts to dominate inducing an accelerated expansion of the universe at the present epoch. We further exhibit the fact that both the leading local and non-local terms can be obtained within the covariant effective field theory of gravity. This scenario thus provides a unified picture of inflation and dark energy in a single framework by means of a purely gravitational action without the usual need of a scalar field.

v1: 6 pages, 3 figures; v2: references added and minor corrections; v3: minor corrections, version published in EPJC

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Cited by in corpus (6)

• Consistent early and late time cosmology from the RG flow of gravity
• Structure formation in the new Deser-Woodard nonlocal gravity model
• Metric for Rotating object in Infrared Corrected Nonlocal Gravity Model
• Leading Gravitational Corrections and a Unified Universe
• Domestic Corpuscular Inflaton
• Spherically symmetric static solutions, newtonian potential and degrees of freedom of a Nonlocal action