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arXiv · 1404.6212

Nonminimal torsion-matter coupling extension of f(T) gravity

Tiberiu Harko·Francisco S. N. Lobo·G. Otalora·Emmanuel N. Saridakis
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Abstract

We construct an extension of f(T) gravity with the inclusion of a non-minimal torsion-matter coupling in the action. The resulting theory is a novel gravitational modification, since it is different from both f(T) gravity, as well as from the non-minimal curvature-matter-coupled theory. The cosmological application of this new theory proves to be very interesting. In particular, we obtain an effective dark energy sector whose equation-of-state parameter can be quintessence or phantom-like, or exhibit the phantom-divide crossing, while for a large range of the model parameters the Universe results in a de Sitter, dark-energy-dominated, accelerating phase. Additionally, we can obtain early-time inflationary solutions too, and thus provide a unified description of the cosmological history.

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Tiberiu Harko, Francisco S. N. Lobo, G. Otalora, Emmanuel N. Saridakis. 2014-06-21. Nonminimal torsion-matter coupling extension of f(T) gravity. https://doi.org/10.1103/physrevd.89.124036

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