  Non-thermal correlations of strongly correlated electron systems and the
far-from-equilibrium properties of phases of condensed matter have become a
topical research area. Here, an overview of the non-linear dynamics found near
continuous zero-temperature phase transitions within the context of effective
temperatures is presented. In particular, we focus on models of critical Kondo
destruction. Such a quantum critical state, where Kondo screening is destroyed
in a critical fashion, is realized in a number of rare earth intermetallics.
This raises the possibility of experimentally testing for the existence of
fluctuation-dissipation relations far from equilibrium in terms of effective
temperatures near quantum criticality. Finally, we present an analysis of a
non-interacting, critical reference system, the pseudogap resonant level model,
in terms of effective temperatures and contrast these results with those
obtained near interacting quantum critical points.
