Non-Abelian Born-infeld cosmology

We investigate homogeneous and isotropic cosmological solutions supported by the SU(2) gauge field governed by the Born-Infeld Lagrangian. In the framework of the Friedmann-Robertson-Walker cosmology with or without the cosmological constant lambda, we derive dynamical systems that give a rather complete description of the space of solutions. For lambda=0 the effective equation of state epsilon(p) is shown to interpolate between p=-epsilon/3 in the regime of the strong field and p=epsilon/3 for the weak field. Correspondingly, the universe starts with zero acceleration and gradually enters the decelerating regime, asymptotically approaching the Tolman solution.