Trace-anomaly driven inflation in f(T) gravity with a cosmological constant

Abstract

In this paper, we have investigated trace-anomaly (TA) driven inflation in Generalized Teleparallel gravity (namely f(T)). A quasi de Sitter (dS) scenario for inflation is proposed like in the case of R-2 gravity. It has been found that in f (T) gravity, the dS solution for inflation is unstable due to the conformal anomaly (CA). As an illustrative example, we have analyzed trace anomaly driven inflation in a T-2 + f(T)-model. Furthermore, a model with a non zero cosmological constant is studied. We have shown that dS solution always remains unstable also in the presence of cosmological constant, but for Anti dS (AdS) case the situation dramatically changes.