Does curvature–dilaton coupling with a Kalb–Ramond field lead to an accelerating Universe?

Abstract

In this work we show that the Universe evolving in a spacetime with torsion (originated from a second rank antisymmetric Kalb-Ramond field) and dilaton is free from any big bang singularity and can have acceleration during the evolution. Both the matter and radiation dominated era have been considered and the role of the dilaton to explain the decelerating phase in the earlier epoch has also been discussed.

Charged black holes in generalized dilaton-axion gravity

“…Symbolically, T µνλ = constant ×H µνλ , and the effective four dimensional version of the theory in terms of the dual axion field ξ, can in general involve a constant parameter in front of the kinetic term of ξ as in Eq. (5.1) (see [36] for a detailed analysis). Under suitable scaling of the ξ field, one can get rid of the constant, thereby restoring the canonical form of the kinetic term of ξ.…”

“…This has been studied in detail in some recent works both in four dimensions [28] and also in the context of higher dimensional Randall-Sundrum [29] scenario [30,31,32]. The effect of the KR field on various other physical phenomena, such as gravitational lensing and redshift [33], neutrino oscillation [34], Cosmic Microwave polarization anisotropy [35], cosmic acceleration [36] etc. have also been explored to look for possible indirect evidences of string theory at low energies.…”