Humboldt-Universität zu Berlin - Faculty of Mathematics and Natural Sciences - Statistical Physics and Nonlinear Dynamics & Stochastic Processes

Justus Kromer - Noise-Controlled Metastability in an Excitable System with Positive Feedback

  • When Jul 02, 2014 from 03:45 to 04:30
  • Where NEW 15 3'101
  • Attendees Justus Kromer
  • iCal

We study the effect of event-triggered positive feedback on a stochastic phase oscillator model operating in the excitable regime. If a noisy excitation leads to an excursion from the stable node, a slow-decaying feedback is applied that pushes the system closer to the oscillatory regime.
In addition to the low-activity excitable state, strong feedback can cause a self-driving effect, i.e. once excursions occur at a high rate the feedback stabilizes the system in a high-activity oscillatory state.
Furthermore, we investigate the role of noise in such systems. Interestingly, noise not only leads to transitions between those metastable states but also controls their occupation probability. As a consequence, noise can be used to tune system properties like variability, which possess giant values for equiprobable states.