Dynamical universality of the contact process

TL;DR

This paper investigates the universal dynamical scaling behaviors of different contact process variants in two dimensions, providing insights into contagion dynamics and methods to precisely locate critical points.

Contribution

It demonstrates the universality of local and global two-time correlators and responses in contact processes, enhancing understanding of non-equilibrium critical phenomena.

Findings

Universal scaling relations confirmed for contact process variants

Global correlators help accurately identify critical points

Scaling functions shape consistent across variants

Abstract

The dynamical relaxation and scaling properties of three different variants of the contact process in two spatial dimensions are analysed. Dynamical contact processes capture a variety of contagious processes such as the spreading of diseases or opinions. The universality of both local and global two-time correlators of the particle-density and the associated linear responses are tested through several scaling relations of the non-equilibrium exponents and the shape of the associated scaling functions. In addition, the dynamical scaling of two-time global correlators can be used as a tool to improve on the determination of the location of critical points.