We apply the de Broglie-Bohm interpretation to the Wheeler-DeWitt equation for the quantum FRW cosmological model with a minimal massless scalar field. We find that the quantum FRW cosmological model has quantum potential dominated solutions that avoid the initial and the final cosmological singularities. It is suggested that the quantum potential and the back-reaction of geometry and matter fi...

Born-Infeld determinantal gravity formulated in Weitzenböck spacetime is discussed in the context of Friedmann-Robertson-Walker (FRW) cosmologies. It is shown how the standard model big bang singularity is absent in certain spatially flat FRW spacetimes, where the high energy regime is characterized by a de Sitter inflationary stage of geometrical character, i.e., without the presence of the in...

We study the late time evolution of flat and negatively curved FRW models with a perfect fluid matter source and a scalar field having an arbitrary non-negative potential function V (φ). We prove using a dynamical systems approach four general results for a large class of non-negative potentials which show that almost always the universe ever expands. In particular, for potentials having a loca...

The Ehlers-Ellis 1+3 formulation of covariant hydrodynamics, when supplemented with covariant radiative transport theory, gives an exact, physically transparent description of the physics of the cosmic microwave background radiation (CMB). Linearisation around a Friedmann-Robertson-Walker (FRW) universe provides a very direct and seamless route through to the linear, gaugeinvariant perturbation...

We consider space-times with two isometries which represent gravitational waves with distinct wavefronts which propagate into exact Friedmann–Robertson–Walker (FRW) universes. The geometry of possible wavefronts is analysed in detail in all three types of FRW models. In the spatially flat and open universes, the wavefronts can be planar or cylindrical; in the closed case they are toroidal. Exac...

for the log derivative of the FRW scale factor, the famous Hubble parameterH(η) = da/dη a . The independent variable is the conformal time η, c is simply related to the adiabatic index of the cosmological fluid, c = 3 2 γ − 1 which was assumed constant by Faraoni, and κ = 0,±1 is the curvature index of the flat, closed, open FRW universe, respectively. For the mathematical considerations of thi...