S. Capozziello, T. Harko, F. S. N. Lobo, G. J. Olmo
Abstract
The nonequivalence between the metric and Palatini formalisms of f(R) gravity is an intriguing feature of these theories. However, in the recently proposed hybrid metric-Palatini gravity, consisting of the superposition of the metric Einstein-Hilbert Lagrangian with an f(; {R}) term constructed à la Palatini, the "true" gravitational field is described by the interpolation of these two nonequivalent approaches. The theory predicts the existence of a light long-range scalar field, which passes the local constraints and affects the galactic and cosmological dynamics. Thus, the theory opens new possibilities for a unified approach, in the same theoretical framework, to the problems of dark energy and dark matter, without distinguishing a priori matter and geometric sources, but taking their dynamics into account under the same standard.
Keywords
Modified: gravity - late-time: cosmic: acceleration - dark: matter - solar: system: tests
International Journal of Modern Physics D
Volume 22, Number 1342, Page 1342006_1
2013 August
