Dario Bambusi GALERKIN AVERAGING METHOD AND POINCARE' NORMAL FORM FOR SOME QUASILINEAR PDEs (346K, pdf) ABSTRACT. We use the Galerkin averaging method to construct a coordinate transformation putting a nonlinear PDE in Poincar\'e normal form up to a remainder of arbitrary order. The abstract theorem we obtain applies to quite general quasilinear equations in one or more space dimensions. Applications to nonlinear wave and heat equations are given. Dynamical consequences are obtained.