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arXiv · 1402.2256

A novel teleparallel dark energy model

Giovanni Otalora
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Abstract

Although equivalent to general relativity, teleparallel gravity is conceptually speaking a completely different theory. In this theory, the gravitational field is described by torsion, not by curvature. By working in this context, a new model is proposed in which the four-derivative of a canonical scalar field representing dark energy is nonminimally coupled to the "vector torsion". This type of coupling is motivated by the fact that a scalar field couples to torsion through its four-derivative, which is consistent with local spacetime kinematics regulated by the de Sitter group $SO(1,4)$. It is found that the current state of accelerated expansion of the Universe corresponds to a late-time attractor that can be (i) a dark-energy-dominated de Sitter solution ($ω_ϕ=-1$), (ii) a quintessence-type solution with $ω_ϕ\geq-1$, or (iii) a phantom-type $ω_ϕ<-1$ dark energy.

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Giovanni Otalora. 2015-11-27. A novel teleparallel dark energy model. https://doi.org/10.1142/s0218271816500255

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