Self-organization of heterogeneous topology and symmetry breaking in networks with adaptive thresholds and rewiring
arXiv:0708.1637 · doi:10.1209/0295-5075/84/10004
Abstract
We study an evolutionary algorithm that locally adapts thresholds and wiring in Random Threshold Networks, based on measurements of a dynamical order parameter. A control parameter determines the probability of threshold adaptations vs. link rewiring. For any , we find spontaneous symmetry breaking into a new class of self-organized networks, characterized by a much higher average connectivity than networks without threshold adaptation (). While and evolved out-degree distributions are independent from for , in-degree distributions become broader when , approaching a power-law. In this limit, time scale separation between threshold adaptions and rewiring also leads to strong correlations between thresholds and in-degree. Finally, evidence is presented that networks converge to self-organized criticality for large .
4 pages revtex, 6 figures