Narrow Results

This paper is devoted to the approach to gravity as a theory of a surface embedded in a flat ambient space. After the brief review of the properties of original theory by Regge and Teitelboim we concentrate on its field-theoretic reformulation, which we call splitting theory. In this theory embedded surfaces are defined through the constant value surfaces of some set of scalar fields in high-dimensional Minkowski space. We obtain an exact expressions for this scalar fields in the case of Friedmann universe. We also discuss the features of quantization procedure for this field theory.

In this work, we study the F (R) gravity with f -essence for the flat and homogeneous Friedman-Robertson-Walker universe. For this model, we have presented the point-like Lagrangian and the corresponding field equations. To describe the dynamics of the universe, we have investigated some cosmological solutions for K, F and h functions. It is shown that these solutions describe the late time accelerated expansion of the Universe.

We consider inflationary scenarios of the supersymmetric quantum cosmology of FRLW models with a scalar field. We use the superfield formalism with a superpotential for the scalar superfield. The probability amplitude solution of the supersymmetric Wheeler-DeWitt equation, gives a probability density from which we can compute mean trajectories that can be parametrized by the scalar. By suitable choices of the superpotential, the resulting evolutions of the scale factor correspond to consistent inflationary scenarios. We show the acceleration, the resulting e-folds and the horizon for several superpotentials.