Cosmology with a long-range repulsive force

We discuss the properties of a cosmology dominated by a charged scalar field with a repulsive, long-range self-interaction. The interaction, in the form of a vector field with a tiny mass, can have a dramatic effect on the evolution of the universe, with interesting consequences – including in some cases accelerated expansion. One characteristic of the model is an oscillating deceleration parameter, which would potentially allow it to be distinguished from other scalar field models such as quintessence.