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arXiv · 1305.3756

Hybrid modified gravity unifying local tests, galactic dynamics and late-time cosmic acceleration

Salvatore Capozziello·Tiberiu Harko·Francisco S. N. Lobo·Gonzalo J. Olmo
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Abstract

The non-equivalence 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 $f(\cal R)$ term constructed à la Palatini, the "true" gravitational field is described by the interpolation of these two non-equivalent 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.

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Salvatore Capozziello, Tiberiu Harko, Francisco S. N. Lobo, Gonzalo J. Olmo. 2013-08-14. Hybrid modified gravity unifying local tests, galactic dynamics and late-time cosmic acceleration. https://doi.org/10.1142/s0218271813420066

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