A dynamic description on phase transfer in a linear Sigma model

Here was derived on a differential equation to describe a time development of an order parameter for a linear Sigma model by using a projective operational analysis. As it is a problem how this non-linear equation soles in future, when obtaining a time development near minimum point of potential, it can be expected to neglect its nonlinear term to obtain a good approximation by solving it with linear approximation. And, it is future problem to adopt contribution from remained non-linear term and to adopt high order contribution (contribution of collision term and so forth). (G.K.)