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Linear growth in power law $f(T)$ gravity

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 نشر من قبل Spyros Basilakos
 تاريخ النشر 2016
  مجال البحث فيزياء
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 تأليف Spyros Basilakos




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We provide for the first time the growth index of linear matter fluctuations of the power law $f(T) propto (-T)^{b}$ gravity model. We find that the asymptotic form of this particular $f(T)$ model is $gamma approx frac{6}{11-6b}$ which obviously extends that of the $Lambda$CDM model, $gamma_{Lambda}approx 6/11$. Finally, we generalize the growth index analysis of $f(T)$ gravity in the case where $gamma$ is allowed to vary with redshift.



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