Solving the $$H_{0}$$ 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 $$H_{0}$$ H 0 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, $$f(T)=\alpha T_{0}\left( 1-e^{-p T / T_{0}}\right) $$ f ( T ) = α T 0 1 - e - p T / T 0 , has the capability to solve the $$H_{0}$$ H 0 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 $$H_{0}$$ H 0 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).

New cosmological constraints on f(T) gravity in light of full Planck-CMB and type Ia supernovae data

“…So larger values of b correspond to the larger values of H 0 . In our present analyses, the parameter b is left free with flat priors, and we find b ∼ Oð10 −4 Þ, the most robust constraint on b in the context of fðTÞ gravity scenario compared to earlier studies on fðTÞ gravity with different perspectives [31][32][33][34][35][37][38][39][41][42][43][44][45]47,48,51,[55][56][57][58][60][61][62]. Finally, therefore, in light of these new perspectives, the fðTÞ gravity scenario investigated in the present work is practically indistinguishable from the ΛCDM model.…”

“…The second main aim of this work is to obtain new observational constraints on the fðTÞ gravity using the full Planck-CMB data, after deriving the relation for the functions Σ and μ in the fðTÞ gravity framework. The fðTÞ gravity has been intensively investigated using geometrical data after computing the modified expansion rate of the Universe HðzÞ [31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46][47][48], and also on subhorizon scales by considering measurements of the growth rate [49][50][51][52][53][54]. The fðTÞ teleparallel gravity is investigated previously with different observational data in [31][32][33][34][35][37][38][39][41][42][43][44][45]47,48,51,[55][56][57][58][59], and in particular with full CMB data in [31,…”

“…The fðTÞ gravity has been intensively investigated using geometrical data after computing the modified expansion rate of the Universe HðzÞ [31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46][47][48], and also on subhorizon scales by considering measurements of the growth rate [49][50][51][52][53][54]. The fðTÞ teleparallel gravity is investigated previously with different observational data in [31][32][33][34][35][37][38][39][41][42][43][44][45]47,48,51,[55][56][57][58][59], and in particular with full CMB data in [31,60,61]. The new ingredient in the present work is to quantify the MG effects parameterized...…”

Updating constraints on phantom crossing f(T) gravity

“…Another study focused on the use of CMB priors to investigate how well-known f (T ) models could address the H 0 tension, in which the power-law form could be a viable option by an increasing uncertainty on the deviation parameter [34]. On the other hand, an exponential form was favored in this aspect when machine learning techniques are considered [40]. In [12] the general requirements of a cosmological model to solve the Hubble and growth tensions are discussed, in a way that certain conditions could be established, which helps in model building.…”

The Hubble constant tension: current status and future perspectives through new cosmological probes

“…The solution to this tension is not an easy task, and many suggestions have been provided by the scientific community. Considering the theoretical scenarios, many researchers have proposed a modification of gravity [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27], in particular the 𝑓 (𝑅) theories [28][29][30][31][32][33][34][35][36][37][38][39][40][41][42], the 𝑓 (𝑇) theories [43][44][45][46][47][48][49][50][51][52][53][54][55][56][57], or the 𝑓 (𝑄) theories [58,59]. It is also important to mention that many alternative cosmological models have been suggested by the scientific community .…”