Modified F(R) HoavaLifshitz gravity: a way to accelerating FRW cosmology

Masud Chaichian (1, 2) , Shin ' Ichi Nojiri (3) , Sergei D Odintsov (4, 5) , Markku Oksanen (1) , Anca Tureanu (1, 2)

1 Department of Physics [Helsinki]
2 HIP - Helsinki Institute of Physics
3 Department of Physics [Nagoya]
4 ICREA - Institució Catalana de Recerca i Estudis Avançats = Catalan Institution for Research and Advanced Studies
5 ICE-CSIC - Institut de Ciencies de l'Espai [Barcelona]

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.

Mots clés: 11.10.Ef; 95.36.+x; 98.80.Cq; 04.50.Kd; 11.25.-w

Masud Chaichian, Shin ' Ichi Nojiri, Sergei D Odintsov, Markku Oksanen, Anca Tureanu. Modified F(R) HoavaLifshitz gravity: a way to accelerating FRW cosmology. Classical and Quantum Gravity, 2010, 27 (18), pp.185021. ⟨10.1088/0264-9381/27/18/185021⟩. ⟨hal-00625167⟩