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DY: Dynamik und Statistische Physik

DY 46: Poster

DY 46.17: Poster

Donnerstag, 27. März 2003, 15:30–18:00, P1

Stochastic differential equations for deterministic chaotic dynamical systems — •Anja Riegert¹, Katrin Gelfert¹, Holger Kantz¹, and Wolfram Just² — ¹Max-Planck-Institut fr Physik komplexer Systeme, 01187 Dresden — ²Institut fr Physik, TU Chemnitz, 09107 Chemnitz

Using techniques borrowed from nonequilibrium statistical mechanics we analyse how fast chaotic degrees of freedom in a low dimensional dynamical system can be modelled in terms of suitable stochastic forces. By time scale separation we derive a Langevin equation directly from the deterministic equations of motion. While the time correlations of the stochastic forces are still short ranged the statistics is determined by the invariant measure of the fast subsystem and deviates from a Gaussian white noise. Thus the approach is able to cope with the computation of exit times. Several steps of our perturbation expansion can be based on rigorous arguments.