Appears in collection : 2015 - T1 - Disordered systems, random spatial processes and some applications

The course consists of two parts. In the first one we give an introduction to the Renormalization Group as a method to study quantum field theory and statistical mechanics models at critical temperature. In the second part we apply these ideas to proving existence and uniqueness of solutions of stochastic PDE's driven by space time white noise. Examples are the KPZ and \phi^4_3 models.