F. Dumortier et H. Kokubu, Chaotic dynamics in Z(2)-equivariant unfoldings of codimension three singularities of vector fields in R-3, ERGOD TH DY, 20, 2000, pp. 85-107
We study the most generic nilpotent singularity of a vector field in R-3 wh
ich is equivariant under reflection with respect to a line, say the z-axis.
We prove the existence of eight equivalence classes for C-0-equivalence, a
ll determined by the 2-jet. We also show that in certain cases, the Z(2)-eq
uivariant unfoldings generically contain codimension one heteroclinic cycle
s which are comparable to the Skil'nikov-type homoclinic cycle in non-equiv
ariant unfoldings. The heteroclinic cycles are accompanied by infinitely ma
ny horseshoes and also have a reasonable possibility of generating suspensi
ons of Henon-Like attractors, and even Lorenz-like attractors.