Logamediate Inflation in f(T) Teleparallel Gravity

Abstract

We study logamediate inflation in the context of f (T ) teleparallel gravity. f (T )-gravity is a generalization of the teleparallel gravity which is formulated on the Weitzenböck spacetime, characterized by the vanishing curvature tensor (absolute parallelism) and the non-vanishing torsion tensor. We consider an f (T )-gravity model which is sourced by a canonical scalar field. Assuming a power-law f (T ) function in the action, we investigate an inflationary universe with a logamediate scale factor. Our results show that, although logamediate inflation is completely ruled out by observational data in the standard inflationary scenario based on Einstein gravity, it can be compatible with the 68% confidence limit joint region of Planck 2015 TT,TE,EE+lowP data in the framework of f (T )-gravity.

Spherically symmetric vacuum in covariant F(T)=T+α2T2+DeBenedictis1, Ilijić2 2016Phys. Rev. D6810612View full textAdd to dashboardCite

“…We make the mild assumption that the full F (T ), whatever it may be, is analytic in T , and hence (16) captures the dominant terms in the Taylor expansion. It also may be that the T 2 contribution may be exact, and many authors have studied specific power-law Lagrangians as an exact theory [30] - [34]. The equations of motion (10), even with T ν ρ = 0 as required for vacuum, are extremely complicated to solve even when frozen to spherical symmetry.…”

Reheating in a modified teleparallel model of inflation

“…Similar to the well-known extension of Einstein-Hilbert action to modified gravity ( f (R) model), the modified teleparallel gravity (f (T ) model) is an extension of the teleparallel model [29,30]. Scalar and tensor perturbations in teleparallel gravity were studied in [41,42]. Power spectrum and spectral index for scalar and tensor modes in f (T ) gravity have been calculated in [42].In this paper, inspired by the above-mentioned models, we will consider inflation in the modified teleparallel model.…”

“…Scalar and tensor perturbations in teleparallel gravity were studied in [41,42]. Power spectrum and spectral index for scalar and tensor modes in f (T ) gravity have been calculated in [42].In this paper, inspired by the above-mentioned models, we will consider inflation in the modified teleparallel model. In a pure teleparallel model, it is not clear how the Universe is warming up after the inflation, and how particles are created.…”

“…Scalar and tensor perturbations in teleparallel gravity were studied in [41,42]. Power spectrum and spectral index for scalar and tensor modes in f (T ) gravity have been calculated in [42].…”

Reconstruction of f ( T ) $f(T)$ -gravity in the absence of matter

“…The f (T ) theories have paid more attention in the last decade to exploring different aspects in astrophysics [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27] and in cosmology [28][29][30][31][32][33][34][35][36][37][38]. Some applications show interesting results, e.g.…”