Real and complex behavior for networks of coupled logistic maps

TL;DR

This paper explores how the structure of networks of coupled logistic maps influences their dynamics, extending classical Julia and Mandelbrot set concepts to complex networked systems using analytical and numerical methods.

Contribution

It introduces a framework for analyzing the dynamics of low-dimensional networks of coupled logistic maps, extending Julia and Mandelbrot sets to networked systems and examining effects of connectivity perturbations.

Findings

Network topology affects Julia set properties.

Perturbations in connectivity alter system dynamics.

Framework sets stage for high-dimensional network analysis.

Abstract

Many natural systems are organized as networks, in which the nodes interact in a time-dependent fashion. The object of our study is to relate connectivity to the temporal behavior of a network in which the nodes are (real or complex) logistic maps, coupled according to a connectivity scheme that obeys certain constrains, but also incorporates random aspects. We investigate in particular the relationship between the system architecture and possible dynamics. In the current paper we focus on establishing the framework, terminology and pertinent questions for low-dimensional networks. A subsequent paper will further address the relationship between hardwiring and dynamics in high-dimensional networks. For networks of both complex and real node-maps, we define extensions of the Julia and Mandelbrot sets traditionally defined in the context of single map iterations. For three different model networks, we use a combination of analytical and numerical tools to illustrate how the system behavior (measured via topological properties of the Julia sets) changes when perturbing the underlying adjacency graph. We differentiate between the effects on dynamics of different perturbations that directly modulate network connectivity: increasing/decreasing edge weights, and altering edge configuration by adding, deleting or moving edges. We discuss the implications of considering a rigorous extension of Fatou-Julia theory known to apply for iterations of single maps, to iterations of ensembles of maps coupled as nodes in a network.