Nonminimally coupled tachyon field in teleparallel gravity
Abstract
We perform a full investigation on dynamics of a new dark energy model in which the fourderivative of a noncanonical scalar field (tachyon) is nonminimally coupled to the vector torsion. Our analysis is done in the framework of teleparallel equivalent of general relativity which is based on torsion instead of curvature. We show that in our model there exists a latetime scaling attractor (point P{sub 4}), corresponding to an accelerating universe with the property that dark energy and dark matter densities are of the same order. Such a point can help to alleviate the cosmological coincidence problem. Existence of this point is the most significant difference between our model and another model in which a canonical scalar field (quintessence) is used instead of tachyon field.
 Authors:
 Department of Physics, Babol Branch, Islamic Azad University, Shariati Street, Babol (Iran, Islamic Republic of)
 Department of Basic Sciences, Babol University of Technology, Shariati Street, Babol (Iran, Islamic Republic of)
 Publication Date:
 OSTI Identifier:
 22525886
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2015; Journal Issue: 04; Other Information: Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; DENSITY; GENERAL RELATIVITY THEORY; GRAVITATION; NONLUMINOUS MATTER; SCALAR FIELDS; TACHYONS; TORSION; UNIVERSE; VECTORS
Citation Formats
Fazlpour, Behnaz, and Banijamali, Ali, Email: b.fazlpour@umz.ac.ir, Email: a.banijamali@nit.ac.ir. Nonminimally coupled tachyon field in teleparallel gravity. United States: N. p., 2015.
Web. doi:10.1088/14757516/2015/04/030.
Fazlpour, Behnaz, & Banijamali, Ali, Email: b.fazlpour@umz.ac.ir, Email: a.banijamali@nit.ac.ir. Nonminimally coupled tachyon field in teleparallel gravity. United States. doi:10.1088/14757516/2015/04/030.
Fazlpour, Behnaz, and Banijamali, Ali, Email: b.fazlpour@umz.ac.ir, Email: a.banijamali@nit.ac.ir. 2015.
"Nonminimally coupled tachyon field in teleparallel gravity". United States.
doi:10.1088/14757516/2015/04/030.
@article{osti_22525886,
title = {Nonminimally coupled tachyon field in teleparallel gravity},
author = {Fazlpour, Behnaz and Banijamali, Ali, Email: b.fazlpour@umz.ac.ir, Email: a.banijamali@nit.ac.ir},
abstractNote = {We perform a full investigation on dynamics of a new dark energy model in which the fourderivative of a noncanonical scalar field (tachyon) is nonminimally coupled to the vector torsion. Our analysis is done in the framework of teleparallel equivalent of general relativity which is based on torsion instead of curvature. We show that in our model there exists a latetime scaling attractor (point P{sub 4}), corresponding to an accelerating universe with the property that dark energy and dark matter densities are of the same order. Such a point can help to alleviate the cosmological coincidence problem. Existence of this point is the most significant difference between our model and another model in which a canonical scalar field (quintessence) is used instead of tachyon field.},
doi = {10.1088/14757516/2015/04/030},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 04,
volume = 2015,
place = {United States},
year = 2015,
month = 4
}

We construct a tachyon teleparallel dark energy model for a homogeneous and isotropic flat universe in which a tachyon as a noncanonical scalar field is nonminimally coupled to gravity in the framework of teleparallel gravity. The explicit form of potential and coupling functions are obtained under the assumption that the Lagrangian admits the Noether symmetry approach. The dynamical behavior of the basic cosmological observables is compared to recent observational data, which implies that the tachyon field may serve as a candidate for dark energy.

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