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arXiv · 1810.05458

Reconstructing bifurcation behavior of a nonlinear dynamical system by introducing weak noise

Debraj Das·Sayan Roy·Shamik Gupta
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Abstract

For a model nonlinear dynamical system, we show how one may obtain its bifurcation behavior by introducing noise into the dynamics and then studying the resulting Langevin dynamics in the weak-noise limit. A suitable quantity to capture the bifurcation behavior in the noisy dynamics is the conditional probability to observe a microscopic configuration at one time, conditioned on the observation of a given configuration at an earlier time. For our model system, this conditional probability is studied by using two complementary approaches, the Fokker-Planck and the path-integral approach. The latter has the advantage of yielding exact closed-form expressions for the conditional probability. All our predictions are in excellent agreement with direct numerical integration of the dynamical equations of motion.

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Debraj Das, Sayan Roy, Shamik Gupta. 2018-10-12. Reconstructing bifurcation behavior of a nonlinear dynamical system by introducing weak noise. https://doi.org/10.1016/j.cnsns.2019.01.018

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