Reconstruction of $F(T)$ gravity in homogeneous backgrounds

Behzad Tajahmad

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arXiv · 1812.10339

Reconstruction of $F(T)$ gravity in homogeneous backgrounds

Behzad Tajahmad

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Abstract

A technique for the reconstruction of the potential for a scalar field in cosmological models based on induced gravity has recently been developed by Alexander Y. Kamenshchik, Alessandro Tronconi, and Giovanni Venturi \cite{ref1}. In this paper, this extended reconstruction method is utilized to investigate the nature of the scalar potentials of the most extended action of $F(T)$-gravity context. First, a general formalism is formulated and then it is utilized for considering some well-known special cases including `Barotropic Fluid', `Cosmological Constant', and `Modified Chaplygin Gas'. The analysis of the results is carried out by the use of the $\mathfrak{B}\text{-function}$ method which has recently been suggested by the author. As we know, assuming a proportional relation between the scale factor of the $x\text{-direction}$ and the scale factors of $y$ and $z$ directions (i.e. $A=B^{m}$) in dealing with LRS Bianchi-I background is prevalent. Pursuant to observational data, the correct physical range of $m$ is extracted. It is demonstrated that, unlike several papers, $m$ is very close to $1$. Some interesting discussions about the modified and generalized Chaplygin gases are performed. The ranges of the amounts of free parameters of the various types of Chaplygin gases are corrected according to observational data. It is demonstrated that the generalized Chaplygin gas model namely $P=-\sigma_{2}/\rho^{\nu}$ may be developed as $P=-\sigma_{2}/\rho^{\nu(t)}$ (i.e. $\nu=const. \longrightarrow \nu=\nu(t)$). Ultimately, by combining ref. \cite{ref1} and the current paper, a general prescription is recommended for the reconstruction of the potentials of alternative theories of gravity (especially $F(R)$ and $F(T)$), and their relevant analysis.

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Behzad Tajahmad. 2018-12-26. Reconstruction of $F(T)$ gravity in homogeneous backgrounds. https://arxiv.org/abs/1812.10339

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