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

Understand

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 $\Lambda$CDM cosmology through a sole parameter.
• Our analysis reveals that this parameter can be slightly different from its $\Lambda$CDM value, however the best-fit value is very close to the $\Lambda$CDM one.