Réversibilité et classification des centres nilpotents
Réversibilité et classification des centres nilpotents
We consider a germ ω of analytic 1-form in ℝ 2 ,0 with 1-jet ydy. We prove that if ω=0 defines a center (i.e all solutions are cycles) there exists an analytic involution of ℝ 2 ,0 preserving the phase portrait of the system. Geometrically this means that analytic nilpotent …