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arXiv · 1103.0719

Notes on $f(T)$ Theories

Yi Zhang·Hui Li·Yungui Gong·Zong-Hong Zhu
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Abstract

The cosmological models based on teleparallel gravity with nonzero torsion are considered. To investigate the evolution of this theory, we consider the phase-space analysis of the $f(T)$ theory. It shows when the tension scalar can be written as an inverse function of $x$ where $x=\rho_{e}/(3m_{pl}^{2}H^{2})$ and $T=g(x)$, the system is an autonomous one. Furthermore,the $\omega_{e}-\omega'_{e}$ phase analysis is given out. We perform the dynamical analysis for the models $f(T)=\beta T\ln(T/T_{0})$ and $f(T)=\alpha m_{pl}^{2}(-T/m_{pl}^{2})^{n}$ particularly. We find that the universe will settle into de-Sitter phase for both models. And we have examined the evolution behavior of the power law form in the $\omega_{ep}-\omega'_{ep}$ plane.

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Yi Zhang, Hui Li, Yungui Gong, Zong-Hong Zhu. 2011-03-03. Notes on $f(T)$ Theories. https://doi.org/10.1088/1475-7516%2F2011%2F07%2F015

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