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arXiv · 0905.4213

Covariant renormalizable gravity and its FRW cosmology

Shin'ichi Nojiri·Sergei D. Odintsov
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Abstract

We consider the diffeomorphism invariant gravity coupled with the ideal fluid in the non-standard way. The Lorentz-invariance of the graviton propagator in such a theory considered as perturbation over flat background turns out to be broken due to non-standard coupling with the ideal fluid. As a result the behavior of the propagator in the ultraviolet/infrared region indicates that some versions of such theory are (super-)renormalizable ones (with appearance of only physical transverse modes). The FRW cosmology in same cases may be different from the one in General Relativity with the possible quintessence/phantom-like inflationary stage.

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Shin'ichi Nojiri, Sergei D. Odintsov. 2010-01-27. Covariant renormalizable gravity and its FRW cosmology. https://doi.org/10.1103/physrevd.81.043001

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