Pseudo-Darwinian evolution of physical flows in complex networks

TL;DR

This paper investigates how different link removal strategies affect the evolution and robustness of complex transport networks, revealing a universal flux decay and the critical role of initial network connectivity.

Contribution

It introduces a 'Pseudo-Darwinian' strategy for network evolution and analyzes its impact on network structure and flux, highlighting the importance of initial links for robustness.

Findings

Flux decreases following a power-law before collapse

Collapse time depends on initial average links per node

Network robustness varies with removal strategy

Abstract

The evolution of complex transport networks is investigated under three strategies of link removal: random, intentional attack and "Pseudo-Darwinian" strategy. At each evolution step and regarding the selected strategy, one removes either a randomly chosen link, or the link carrying the strongest flux, or the link with the weakest flux, respectively. We study how the network structure and the total flux between randomly chosen source and drain nodes evolve. We discover a universal power-law decrease of the total flux, followed by an abrupt transport collapse. The time of collapse is shown to be determined by the average number of links per node in the initial network, highlighting the importance of this network property for ensuring safe and robust transport against random failures, intentional attacks and maintenance cost optimizations.