Phantom-like GCG and the constraints of its parameters via cosmological dynamics

We extend the equation of state of GCG (Generalized Chaplygin Gas) to w<−1 regime and show, from the point of view of dynamics, that the parameters of GCG should be in the range of 0<α<1. Also, dynamical analysis indicates that the phase wg=−1 is a dynamical attractor and the equation of state of GCG approaches it from either wg>−1 or wg<−1 depending on the choice of its initial cosmic density parameter and the ratio of pressure to critical energy density.