A Note on Helffer-Sj\"ostrand Representation for a Ginzburg-Landau Process

In this work, we explore a link between an unbounded spin system given by a system of stochastic differential equations and a random walk. This allows us to study the decay of the (co)variance of functions with respect to time. We extend here the previous work of T. Bodineau and G. Graham to a more general class of graph and potential.