Gaussian processes and effective field theory of $f(T)$ gravity under the $H_0$ tension

TL;DR

This paper employs Gaussian processes within an effective field theory framework of torsional gravity to reconstruct $f(T)$ models that can address the $H_0$ tension, fitting observational data with high accuracy.

Contribution

It introduces a model-independent reconstruction of $f(T)$ gravity using Gaussian processes and observational data, providing a new approach to modify background evolution in cosmology.

Findings

Reconstructed $f(T)$ functions consistent with data

Identified a family of functions producing desired background evolution

Derived an analytic expression fitting cosmological observations well

Abstract

We consider the effective field theory formulation of torsional gravity in a cosmological framework to alter the background evolution. Then we use the latest $H_0$ measurement from the SH0ES Team as well as observational Hubble data from cosmic chronometer (CC) and radial baryon acoustic oscillations (BAO) and we reconstruct the $f(T)$ form in a model-independent way by applying Gaussian processes. Since the special square-root term does not affect the evolution at the background level, we finally summarize a family of functions that can produce the background evolution required by the data. Lastly, performing a fitting using polynomial functions, and implementing the Bayesian Information Criterion (BIC), we find an analytic expression that may describe the cosmological evolution in great agreement with observations.