Mitchell Institute for Fundamental Physics & Astronomy
College Station, Texas 77843
In this talk I will examine transport in a holographic model in which the dynamics of the charged degrees of freedom is described by the non-linear Dirac-- Born--Infeld (DBI) action. The generic structure of the DC conductivity matrix for these theories is extremely rich. In the probe DBI limit the model reproduces the anomalous temperature dependence of the resistivity and Hall angle of the cuprate strange metal. These scaling laws would not be present without the non-linear dynamics encoded by the DBI interactions. This model provides explicit examples in which transport is controlled by different relaxation times. On the other hand, when only one quantity sets the temperature scale of the system, the Hall angle and DC conductivity typically exhibit the same temperature behavior. I illustrate this point with new fully-backreacted dyonic black brane solutions.