A Simple Model for Nonexponential Relaxation in Complex Dynamics
  The nonexponential relaxation ocurring in complex dynamics manifested in a wide variety of systems is analyzed through a simple model of diffusion in phase space. It is found that the inability of the system to find its equilibrium state in any time scale becomes apparent in an effective temperature field which leads to a hierarchy of relaxation times responsible for the slow relaxation phenomena. 
A. Perez-Madrid