EXTENSIONS OF THE NOTION OF CHAOTIC AREA IN 2ND-ORDER ENDOMORPHISMS

Properties of chaotic areas (i.e. invariant domains of points positively stable in the Poisson's sense) of non-invertible maps of the plane are studied by using the method of critical curves (two-dimensional extension of the notion of critical points in the one-dimensional case). The classical situation is that of a chaotic area bounded by a finite number of critical curves segments. This paper considers another class of chaotic areas bounded by the union of critical curves segments and segments of the unstable manifold of a saddle fixed point, or that of saddle. cycle (periodic point). Different configurations are examined, as their bifurcations when a map parameter varies.