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arXiv · 1109.1468

Scale invariance and a gravitational model with non-eternal inflation

Carlos Herdeiro·Shinji Hirano
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Abstract

We propose a 3 + 1 dimensional model of gravity which results in inflation at early times, followed by radiation- and matter-dominated epochs and a subsequent acceleration at late times. Both the inflation and late time acceleration are nearly de Sitter with a large hierarchy between the effective cosmological constants. There is no scalar field agent of inflation, and the transition from the inflation to the radiation-dominated period is smooth. This model is designed so that it yields, at the cost of giving up on Lorentz invariance in the gravitational sector, the Dirac-Born-Infeld type conformal scalar theory when the universe is conformally flat. It, however, resembles Einstein's gravity with the Gibbons-Hawking-York boundary term in weakly curved space-times.

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Carlos Herdeiro, Shinji Hirano. 2012-04-25. Scale invariance and a gravitational model with non-eternal inflation. https://doi.org/10.1088/1475-7516%2F2012%2F05%2F031

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