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

Gudekli E., MYRZAKULOV N., YERZHANOV K., MYRZAKULOV R.

ASTROPHYSICS AND SPACE SCIENCE, vol.357, no.1, 2015 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 357 Issue: 1
  • Publication Date: 2015
  • Doi Number: 10.1007/s10509-015-2269-8
  • Journal Name: ASTROPHYSICS AND SPACE SCIENCE
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Keywords: Dark energy, f(T) gravity, Cosmological constant, PROBE WMAP OBSERVATIONS, PHASE-TRANSITION, UNIVERSE, MODELS, VACUUM, R-2-INFLATION, PERTURBATIONS, DYNAMICS, TORSION
  • Istanbul University Affiliated: Yes

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 R2 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 T2+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.

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.