http://arxiv.org/abs/1601.03955
In the flat Friedmann-Lema\^{\i}tre-Robertson-Walker (FLRW) geometry, we consider the expansion of the universe powered by the gravitationally induced `adiabatic’ matter creation. To demonstrate how matter creation works well with the expanding universe, we have considered a general creation rate and analyzed this rate in the framework of dynamical analysis. The dynamical analysis hints the presence of a non-singular universe (without the big bang singularity) with two successive accelerated phases, one at the very early phase of the universe (i.e., inflation), and the other one describes the current accelerating universe, where this early, late accelerated phases are associated with an unstable fixed point (i.e., repeller) and a stable fixed (attractor) points, respectively. We have described this phenomena by analytic solutions of the Hubble function and the scale factor of the FLRW universe. Using Jacobi Last multiplier method, we have found a Lagrangian for this matter creation rate describing this scenario of the universe. To match with our early physics results, we introduce an equivalent dynamics driven by a single scalar field and discussed the associated observable parameters compared them with the latest PLANCK data sets. Then introducing the teleparallel modified gravity, we have established an equivalent gravitational theory in the framework of matter creation. Further, introducing an equivalence between matter creation and decaying vacuum, we have found an equivalent decaying vacuum model. Finally, we have discussed a model independent test, cosmography, for the present matter creation model.
S. Pan, J. Haro, A. Paliathanasis, et. al.
Mon, 18 Jan 16
13/50
Comments: 20 pages, No figures, Comments are welcome !