T. Faria, Normal forms for semilinear functional differential equations in Banach spaces and applications. Part II, DISCR C D S, 7(1), 2001, pp. 155-176
A normal form theory for functional differential equations in Banach spaces
of retarded type is addressed. The theory is based on a formal adjoint the
ory for the linearized equation at an equilibrium and on the existence of c
enter manifolds for perturbed inhomogeneous equations, established in the f
irst part of this work under weaker hypotheses than those that usually appe
ar in the literature. Based on these results, an algorithm to compute norma
l forms on finite dimensional invariant manifolds of the origin is presente
d. Such normal forms are important in obtaining the ordinary differential e
quation giving the flow on center manifolds explicitly in terms of the orig
inal functional differential equation. Applications to Bogdanov-Takens and
Hopf bifurcations are presented.