Abstract

We discuss an explicit example of a map of the plane R 2 with a nontrivial attracting set. In particular, we are concerned with the concept of rotation number introduced by Poincare for maps of the circle and its subsequent extension by Birkhoff to maps of the annulus. The use of rotation number allows nontrivial attractors to be distinguished. The map we discuss has an attracting set containing a set of orbits with infinitely many different rotation numbers. We obtain the map by considering an Euler iteration of a family of vector fields originally described by Arnold and find that the resulting Euler map undergoes some bifurcations which are analogous to those of the family of vector fields. Specifically, there are Hopf bifurcations where changes of stability of a fixed point result in the creation of an attracting circle. The circle which grows from the fixed point is then shown to undergo structural changes giving nontrivial attracting sets. This arises from Euler map behaviour for which the corresponding vector field behaviour is a heteroclinic saddle connection. It is possible to give an explicit trapping region for the Euler map which contains the attracting set and to describe some of its properties. Finally, an analogy is drawn with attracting sets which arise for forced oscillators.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.