English

The contact process over a dynamical d-regular graph

Probability 2021-11-24 v1

Abstract

We consider the contact process on a dynamic graph defined as a random dd-regular graph with a stationary edge-switching dynamics. In this graph dynamics, independently of the contact process state, each pair {e1,e2}\{e_1,e_2\} of edges of the graph is replaced by new edges {e1,e2}\{e_1',e_2'\} in a crossing fashion: each of e1,e2e_1',e_2' contains one vertex of e1e_1 and one vertex of e2e_2. As the number of vertices of the graph is taken to infinity, we scale the rate of switching in a way that any fixed edge is involved in a switching with a rate that approaches a limiting value v\mathsf{v}, so that locally the switching is seen in the same time scale as that of the contact process. We prove that if the infection rate of the contact process is above a threshold value λˉ\bar{\lambda} (depending on dd and v\mathsf{v}), then the infection survives for a time that grows exponentially with the size of the graph. By proving that λˉ\bar{\lambda} is strictly smaller than the lower critical infection rate of the contact process on the infinite dd-regular tree, we show that there are values of λ\lambda for which the infection dies out in logarithmic time in the static graph but survives exponentially long in the dynamic graph.

Keywords

Cite

@article{arxiv.2111.11757,
  title  = {The contact process over a dynamical d-regular graph},
  author = {Gabriel Leite Baptista da Silva and Roberto Imbuzeiro Oliveira and Daniel Valesin},
  journal= {arXiv preprint arXiv:2111.11757},
  year   = {2021}
}

Comments

35 pages, 3 figures

R2 v1 2026-06-24T07:48:39.815Z