ABSTRACT
This chapter focuses on some aspects of the non-equilibrium dynamics of a system in the vicinity of a phase transition: how does a system behave when cooled below the critical temperature or when, at a fixed temperature, it is moved away from equilibrium? A first question deals with the appearance of order in an initially disordered system. A second one concerns the return to equilibrium after a perturbation. In the present chapter, these problems are addressed via an equation describing in a phenomenological way the weakly non-equilibrium dynamics of the order parameter characterising the system in the vicinity of a phase transition.
