Gaussian Processes and Effective Field Theory of f(T) Gravity under the H ₀ Tension

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 and radial baryon acoustic oscillations, 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, we find an analytic expression that may describe the cosmological evolution in great agreement with observations.

Quasinormal modes of black holes in f(T) gravity

“…The simplest nonlinear torsional modified gravity is f (T ) gravity, which has the advantage that its field equations have up to second order derivatives. Its cosmological applications prove to be very interesting [21][22][23][24][25][26][27] and the theory has been shown to be in agreement with observations [28][29][30][31][32][33][34]. Furthermore, the black holes solutions in f (T ) gravity have been investigated in detail .…”

Finite-time cosmological singularities and the possible fate of the Universe

“…Now from this scale factor (285), one can describe a variety of finite-time singularities as follows:…”

Neural network reconstruction of H'(z) and its application in teleparallel gravity

“…Other measurements exist that hold the promise of offering new calculations of H 0 that do not rely on electromagnetic observations such as the novel approach of gravitational wave standard sirens [26] but the precision of such methods is not competitive with standard approaches as of yet. In this context, we endeavour to extend the literature in the direction of producing nonparametric estimates of the Hubble parameter together with its derivative which are core to a number of important themes of research such as cosmography [27][28][29] and modified gravity [30][31][32][33][34].…”

“…In refs. [30,31,33] the GP approach was applied to the f (T ) functional with reconstructions of both the mean and uncertainties of the functional form, which was later extended to include growth data in ref. [34].…”

“…Finally, ref. [31] extended some of this work to incorporate f (T ) gravity as an effective field theory. All the reconstructions were undertaken via the GP approach in conjunction with a general f (T ) dominated universe without assuming a specific form of the arbitrary Lagrangian in eq.…”