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arXiv · 1211.1778

Matter Density Perturbations in Modified Teleparallel Theories

Yi-Peng Wu·Chao-Qiang Geng
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Abstract

We study the matter density perturbations in modified teleparallel gravity theories, where extra degrees of freedom arise from the local Lorentz violation in the tangent space. We formulate a vierbein perturbation with variables addressing all the 16 components of the vierbein field. By assuming the perfect fluid matter source, we examine the cosmological implication of the 6 unfamiliar new degrees of freedom in modified $f(T)$ gravity theories. We find that despite the new modes in the vierbein scenario provide no explicit significant effect in the small-scale regime, they exhibit some deviation from the standard general relativity results in super-horizon scales.

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Yi-Peng Wu, Chao-Qiang Geng. 2012-11-08. Matter Density Perturbations in Modified Teleparallel Theories. https://doi.org/10.1007/jhep11(2012)142

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