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arXiv · 1001.4102

Modified F(R) Horava-Lifshitz gravity: a way to accelerating FRW cosmology

Masud Chaichian·Shin'ichi Nojiri·Sergei D. Odintsov·Markku Oksanen·Anca Tureanu
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Abstract

We propose a general approach for the construction of modified gravity which is invariant under foliation-preserving diffeomorphisms. Special attention is paid to the formulation of modified $F(R)$ Hořava-Lifshitz gravity (FRHL), whose Hamiltonian structure is studied. It is demonstrated that the spatially-flat FRW equations of FRHL are consistent with the constraint equations. The analysis of de Sitter solutions for several versions of FRHL indicates that the unification of the early-time inflation with the late-time acceleration is possible. It is shown that a special choice of parameters for FRHL leads to the same spatially-flat FRW equations as in the case of traditional $F(R)$-gravity. Finally, an essentially most general modified Hořava-Lifshitz gravity is proposed, motivated by its fully diffeomorphism-invariant counterpart, with the restriction that the action does not contain derivatives higher than the second order with respect to the time coordinate.

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Masud Chaichian, Shin'ichi Nojiri, Sergei D. Odintsov, Markku Oksanen, Anca Tureanu. 2012-06-05. Modified F(R) Horava-Lifshitz gravity: a way to accelerating FRW cosmology. https://doi.org/10.1088/0264-9381%2F27%2F18%2F185021

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