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arXiv · 1005.4574

Cosmological evolution in exponential gravity

Kazuharu Bamba·Chao-Qiang Geng·Chung-Chi Lee
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Abstract

We explore the cosmological evolution in the exponential gravity $f(R)=R +c_1 (1-e^{- c_2 R})$ ($c_{1, 2} = \mathrm{constant}$). We summarize various viability conditions and explicitly demonstrate that the late-time cosmic acceleration following the matter-dominated stage can be realized. We also study the equation of state for dark energy and confirm that the crossing of the phantom divide from the phantom phase to the non-phantom (quintessence) one can occur. Furthermore, we illustrate that the cosmological horizon entropy globally increases with time.

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Kazuharu Bamba, Chao-Qiang Geng, Chung-Chi Lee. 2010-05-25. Cosmological evolution in exponential gravity. https://doi.org/10.1088/1475-7516/2010/08/021

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