TITLE:
Higher-Order Effects in Two-Layer Interconnected Networks
AUTHORS:
Yuqi Qiao, Haiying Wang
KEYWORDS:
Cooperative Games, Multilayer Networks, Higher-Order Interactions, Propagation Dynamics, Bistability, Mean-Field Theory
JOURNAL NAME:
Open Journal of Applied Sciences,
Vol.15 No.12,
December
15,
2025
ABSTRACT: The study of spreading dynamics in two-layer network systems is of great importance for understanding various real-world propagation phenomena, such as disease transmission and information diffusion. In this paper, we investigate the impact of higher-order structures—specifically, triangular interactions—on contagion processes within a two-layer network, by integrating the SIS epidemic model with a simplicial complex framework. We derive mean-field equations to characterize the system dynamics, analyze the steady-state solutions and their stability, and validate the theoretical findings through numerical simulations. Our results demonstrate that the presence of higher-order structures significantly enhances the spreading capability and induces bistability phenomena. Furthermore, both the inter-layer coupling strength and the asymmetry in node population size are shown to influence the infection density in each layer. This study provides theoretical insights into higher-order contagion mechanisms in multilayer networks and offers novel perspectives for designing effective spread control strategies.