Quintom phase-space: Beyond the exponential potential

We investigate the phase-space structure of the quintom dark energy paradigm in the framework of spatially flat and homogeneous universe. We have also included radiation and dark matter, both matter components are described as perfect fluids. Considering arbitrary decoupled potentials, we find certain general conditions under which the phantom-dominated solution is a late time attractor, generalizing previous results found for the case of an exponential potential. Center Manifold Theory is employed to obtain sufficient conditions for the instability of de Sitter solution either with phantom or quintessence potential dominance. (C) 2014 The Authors. Published by Elsevier B.V.