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arXiv · 1208.2790

Generalized modified gravity with the second order acceleration equation

Changjun Gao
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Abstract

In the theories of generalized modified gravity, the acceleration equation is generally fourth order. So it is hard to analyze the evolution of the Universe. In this paper, we present a class of generalized modified gravity theories which have the acceleration equation of second order derivative. Then both the cosmic evolution and the weak-field limit of the theories are easily investigated. We find that not only the Big-bang singularity problem but also the current cosmic acceleration problem could be easily dealt with.

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BibTeXRIS

Changjun Gao. 2012-10-29. Generalized modified gravity with the second order acceleration equation. https://doi.org/10.1103/physrevd.86.103512

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