Work

Constructing minimal models for complex system dynamics

Year: 2015

Type: article

Abstract: One of the strengths of statistical physics is the ability to reduce macroscopic observations into microscopic models, offering a mechanistic description of a system’s dynamics. This paradigm, rooted in Boltzmann’s gas theory, has found applications from magnetic phenomena to subcellular processes and epidemic spreading. Yet, each of these advances were the result of decades of meticulous model building and validation, which are impossible to replicate in most complex biological, social or technological systems that lack accurate microscopic models. Here we develop a method to infer the microscopic dynamics of a complex system from observations of its response to external perturbations, allowing us to construct the most general class of nonlinear pairwise dynamics that are guaranteed to recover the observed behaviour. The result, which we test against both numerical and empirical data, is an effective dynamic model that can predict the system’s behaviour and provide crucial insights into its inner workings. In statistical physics, the observable macroscopic behaviour of a system is obtained from a microscopic model of its components. Here, the authors extend this approach to systems with no known microscopic dynamics, by looking at the system’s response to external perturbations.

Source: Nature Communications

DOI: 10.1038/ncomms8186

Authors: Baruch Barzel, Yang-Yu Liu, Albert-László Barabási