We consider the scenario emerging from the dynamics of a generalized Born-Infeld theory. The equation of state describing this system is given in terms of the energy density $\rho$ and pressure p by the relationship $p=-A/{\rho }^{\alpha },$ where A is a positive constant and $0<\mathrm{}\alpha <~1.$ We discuss the conditions under which homogeneity arises and show that this equation of state describes the evolution of a universe evolving from a phase dominated by nonrelativistic matter to a phase dominated by a cosmological constant via an intermediate period where the effective equation of state is given by $p=\alpha \rho .$

• Received 11 February 2002

DOI:https://doi.org/10.1103/PhysRevD.66.043507