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arXiv · 1608.01960

Observational Constraints on $f(T)$ gravity from varying fundamental constants

Rafael C. Nunes·Alexander Bonilla·Supriya Pan·Emmanuel N. Saridakis
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Abstract

We use observations related to the variation of fundamental constants, in order to impose constraints on the viable and most used $f(T)$ gravity models. In particular, for the fine-structure constant we use direct measurements obtained by different spectrographic methods, while for the effective Newton's constant we use a model-dependent reconstruction, using direct observational Hubble parameter data, in order to investigate its temporal evolution. We consider two $f(T)$ models and we quantify their deviation from $Λ$CDM cosmology through a sole parameter. Our analysis reveals that this parameter can be slightly different from its $Λ$CDM value, however the best-fit value is very close to the $Λ$CDM one. Hence, $f(T)$ gravity is consistent with observations, nevertheless, as every modified gravity, it may exhibit only small deviations from $Λ$CDM cosmology, a feature that must be taken into account in any $f(T)$ model-building.

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Rafael C. Nunes, Alexander Bonilla, Supriya Pan, Emmanuel N. Saridakis. 2017-04-17. Observational Constraints on $f(T)$ gravity from varying fundamental constants. https://doi.org/10.1140/epjc%2Fs10052-017-4798-5

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