Preprint of the project: DFG Priority Research Program: DANSE

Connecting orbits in highdimensional dynamical systems

15/97 Wolf-Jürgen Beyn, Matthias Stiefenhofer.
A direct approach to homoclinic orbits in the fast dynamics of singularly perturbed systems


Homoclinic orbits in the fast dynamics of singular perturbation problems are usually analyzed by a combination of Fenichel's invariant manifold theory with general transversality arguments (the Exchange Lemma). In this paper an alternative direct approach is developed which uses a two-time scaling and a contraction argument in exponentially weighted spaces. Homoclinic orbits with one fast transition are treated and it is shown how epsilon-expansions can be extracted rigorously from this approach. The result is applied to a singularly perturbed Bogdanov point in the FitzHugh-Nagumo system.