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arXiv · 1305.5896

Cosmological dynamics of tachyonic teleparallel dark energy

G. Otalora
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Abstract

A detailed dynamical analysis of the tachyonic teleparallel dark energy model, in which a non-canonical scalar field (tachyon field) is non-minimally coupled to gravitation, is performed. It is found that, when the non-minimal coupling is ruled by a dynamically changing coefficient $α\equiv f_{,ϕ}/\sqrt{f}$, with $f(ϕ)$ an arbitrary function of the scalar field $ϕ$, the universe may experience a field-matter-dominated era "$ϕ$MDE", in which it has some portions of the energy density of $ϕ$ in the matter dominated era. This is the most significant difference in relation to the so-called teleparallel dark energy scenario, in which a canonical scalar field (quintessence) is non-minimally coupled to gravitation.

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G. Otalora. 2013-08-31. Cosmological dynamics of tachyonic teleparallel dark energy. https://doi.org/10.1103/physrevd.88.063505

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