Solving the H tension in f(T) gravity through Bayesian machine learning

Abstract

Bayesian Machine Learning (BML) and strong lensing time delay (SLTD) techniques are used in order to tackle the H tension in f(T) gravity. The power of BML relies on employing a model-based generative process which already plays an important role in different domains of cosmology and astrophysics, being the present work a further proof of this. Three viable f(T) models are considered: a power law, an exponential, and a squared exponential model. The learned constraints and respective results indicate that the exponential model, f(T)=αT0(1-e-pT/T0), has the capability to solve the H tension quite efficiently. The forecasting power and robustness of the method are shown by considering different redshift ranges and parameters for the lenses and sources involved. The lesson learned is that these values can strongly affect our understanding of the H tension, as it does happen in the case of the model considered. The resulting constraints of the learning method are eventually validated by using the observational Hubble data (OHD).