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arXiv · 1212.2079

Variety of cosmic acceleration models from massive $F(R)$ bigravity

Shin'ichi Nojiri·Sergei D. Odintsov·Norihito Shirai
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Abstract

We study the accelerating cosmology in massive $F(R)$ bigravity via the reconstruction scheme. The consistent solution of the FRW equations is presented: it includes Big and Little Rip, quintessence, de Sitter and decelerating universes described by the physical $g$ metric while the corresponding solution of the universe described by the reference $f$ metric is also found. It is demonstrated that in general the cosmological singularities of $g$ metric are not always manifested as cosmological singularities of the reference $f$ metric. We give two consistent ways to describe the Big and Little Rip, quintessence, de Sitter and decelerating universes. In one of the consistent solutions, the two metrics $g$ and $f$ coincide with each other, which may indicate the connection with the convenient single metric background formulation. For another solution, where two metrics $g$ and $f$ do not coincide with each other, here always appears super-luminal mode.

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Shin'ichi Nojiri, Sergei D. Odintsov, Norihito Shirai. 2013-05-19. Variety of cosmic acceleration models from massive $F(R)$ bigravity. https://doi.org/10.1088/1475-7516%2F2013%2F05%2F020

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