Generalized DBI quintessence

We investigate the phase space of a quintessence theory governed by a generalized version of the DBI action, using a combination of numeric and analytic methods. The additional degrees of freedom lead to a vastly richer phase-space structure, where the field covers the full equation of state parameter space: -1 < 1. We find many nontrivial solution curves to the equations of motion which indicate that DBI quintessence is an interesting candidate for a viable k-essence model.