The growth of matter perturbations in the f(T) gravity

Abstract

In this paper, we study the growth index of matter density perturbations for the power law model in $f(T)$ gravity. Using the parametrization $γ(z)=γ_0+γ_1 {z\over 1+z}$ for the growth index, which approximates the real evolution of $γ(z)$ very well, and the observational data of the growth factor, we find that, at $1σ$ confidence level, the power law model in $f(T)$ gravity is consistent with the observations, since the obtained theoretical values of $γ_0$ and $γ_1$ are in the allowed region.

11 pages 4 figures