Unified dark energy from Chiral-Quintom model with a mixed potential in Friedmann–Lemaître–Robertson–Walker cosmology

Abstract

For a spatially Friedmann–Lemaître–Robertson–Walker cosmology, we propose a multi-scalar field gravitational model. Specifically, we consider a two-scalar field cosmological model in which the kinetic components of the scalar fields establish a two-dimensional sphere of Lorentzian signature. For our Chiral-Quintom model we choose a mixed potential term Vleft( phi ,psi right) =V_{0}e^{lambda phi }+U_{0}e^{kappa phi }psi ^{frac{1}{sigma } } and we investigate the asymptotic limits of the cosmological parameters. This model for U_{0}=0, provides a generalization of the hyperbolic inflation where the equation of the state parameter can cross the phantom divide line. When U_{0}ne 0 we observe that this cosmological model exhibits asymptotic solutions that encompass accelerated universes, big rip singularities, and dust-like solutions. Hence, this multi-scalar field model it can be regarded as as a dark energy unify model which describes a variety of asymptotic cosmological scenarios.