- Letter
Phase transition in the susceptible-infected model on hypernetworks
Phys. Rev. E 112, L012302 – Published 28 July, 2025
DOI: https://doi.org/10.1103/hylh-tzkk
Abstract
We derive the master equations for the Susceptible-Infected (SI) model on general hypernetworks with -body interactions. We solve these equations exactly for infinite -regular hypernetworks, and obtain an explicit solution for the expected infection level as a function of time. The solution shows that the epidemic spreads out to the entire population as if and only if the initial infection level exceeds a positive threshold value. This phase transition is a high-order interaction effect, which is absent with pairwise interactions.