Parts | Days | Selection | Search | Updates | Downloads | Help

DY: Fachverband Dynamik und Statistische Physik

DY 35: Statistical Physics of Biological Systems I (joint session BP/DY)

DY 35.6: Talk

Thursday, March 30, 2023, 11:15–11:30, TOE 317

Collective Dynamics of Multi-Scale Interacting Complex Systems — •Fabrizio Olmeda^1,2 and Steffen Rulands^1,3 — ¹Max Planck Institute for the Physics of Complex Systems, Dresden, Germany — ²IST Austria, Vienna, Austria — ³Ludwigs-Maximilians-Universitat Munchen, Arnold Sommerfeld Center for Theoretical Physics, Munich, Germany

Understanding the conditions under which complex systems are stable is pivotal for understanding their response to perturbations. Theoretical work has shown that for global interactions between components a minimal complex system is stable if the standard deviation of linearised interaction rates is sufficiently small. In biological systems, which often contain a small number of important and interactions are mediated by diffusing agents, stochasticity and non-locality may influence stability. Here, we generalise these results to stochastic, spatial systems with interaction on multiple length scales. Starting from a microscopic description we derive a coarse-grained field theory and identify a transition between a regime defined by giant density fluctuations and one exhibiting a spatial instability with a finite wave length. The latter is suppressed by non-reciprocity in the interactions between components. Our work provides a rigorous framework to infer collective dynamics and stability in complex systems, with applications ranging from ecosystems to morphogenesis.