Phys Rev E Stat Nonlin Soft Matter Phys. 2012 Apr;85(4):045102. doi: 10.1103/PhysRevE.85.045102. Epub 2012 Apr 27.

Multiplexity-facilitated cascades in networks.

Physical review. E, Statistical, nonlinear, and soft matter physics

Charles D Brummitt, Kyu-Min Lee, K-I Goh

PMID: 22680529 DOI: 10.1103/PhysRevE.85.045102

Abstract

Elements of networks interact in many ways, so modeling them with graphs requires multiple types of edges (or network layers). Here we show that such multiplex networks are generically more vulnerable to global cascades than simplex networks. We generalize the threshold cascade model [Watts, Proc. Natl. Acad. Sci. USA 99, 5766 (2002)] to multiplex networks, in which a node activates if a sufficiently large fraction of neighbors in any layer are active. We show that both combining layers (i.e., realizing other interactions play a role) and splitting a network into layers (i.e., recognizing distinct kinds of interactions) facilitate cascades. Notably, layers unsusceptible to global cascades can cooperatively achieve them if coupled. On one hand, this suggests fundamental limitations on predicting cascades without full knowledge of a system's multiplexity; on the other hand, it offers feasible means to control cascades by introducing or removing sparse layers in an existing network.

Publication Types

• Journal Article
• Research Support, Non-U.S. Gov't