Constraining f(T, B) teleparallel gravity from energy conditions

Abstract

f(T, B) teleparallel gravity is a recently proposed straightforward generalization of the popular f(T) teleparallel gravity by the incorporation of a boundary term B=2e∂i(eTi)=▽iTi where T denote the torsion scalar (Bahamonde et al., 2015). In this work, I investigate the viability of some well motivated f(T, B) teleparallel gravity models of the forms f=αBn+βTm,f=αBnTm and f=αlog(B)+βT where α, β, n and m are free parameters from the inequalities imposed the weak energy condition. I use the recent estimates of Hubble, deceleration, jerk and snap parameters in finding corners in parameter spaces for the cosmological models for which the energy density remain positive and the weak energy condition (i.e, ρ+p≥0, where p and ρ represent respectively the cosmological pressure and energy density) attains a minute positive value, as this implies the EoS parameter ω=p/ρ≃−1 and therefore consistent with an accelerating universe.