Cosmological dynamics of the general non-canonical scalar field models

Abstract

We extend the investigation of cosmological dynamics of the general non-canonical scalar field models by dynamical system techniques for a broad class of potentials and coupling functions. In other words, we do not restrict the analysis to exponential or power-law potentials and coupling functions. This type of investigation helps in understanding the general properties of a class of cosmological models. In order to better understand the phase space of the models, we investigate the various special cases and discuss the stability and viability issues. Performing a detailed stability analysis, we show that it is possible to describe the cosmic history of the universe at the background level namely the early radiation dominated era, intermediate matter dominated era and the late time dark energy domination. Moreover, we find that we can identify a broad class of potentials and coupling functions for which it is possible to get an appealing unified description of dark matter and dark energy. The results obtained here, therefore, enlarge the previous analyses wherein only a specific potential and coupling functions describes the unification of dark sectors. Further, we also observe that a specific scenario can also possibly explain the phenomenon of slow-roll inflationary exit. arXiv:1812.07836v2 [gr-qc]

Dynamical system analysis of logotropic dark fluid with a power law in the rest-mass energy density

“…Generally, the Center Manifold theory can be employed to achieve the stability criteria of the point. However, the stability of this type of point can also be achieved by numerically perturbing the solution trajectories near the point as N −→ ∞ and this method is now a promising one in the literature (see for example [48]). In figure (3) the trajectories of the solutions are plotted numerically for ω m = 0 and A = 0.25 along x axis, y axis and H axis where the initial conditions are chosen very close to the coordinates of the point.…”

Cosmological dynamics and bifurcation analysis of the general non-minimal coupled scalar field models

“…One can also predict the sensitivity of the solution to initial conditions. Dynamical system methods have been used extensively in cosmology; see [3][4][5][6][7][8][9][10][11][12][13][14][15] for relevant work and [16] for a comprehensive review.…”

Cosmological dynamics and bifurcation analysis of the general non-minimally coupled scalar field models

“…One can also predict the sensitivity of the solution to the initial conditions. Dynamical system methods have been used extensively in cosmology; see [3][4][5][6][7][8][9][10] for relevant recent work and [11] for a recent comprehensive review.…”