Universal scaling behavior of directed percolation and the pair contact process in an external field

TL;DR

This paper investigates the universal scaling behavior of directed percolation and the pair contact process under an external field, demonstrating their shared scaling function and deriving their equations of state.

Contribution

It provides numerical and analytical evidence that both models share the same universal scaling function and derives their mean-field equations of state.

Findings

Both models share the same universal scaling function.

The mean-field equation of state for the pair contact process matches that of directed percolation.

Numerical analysis confirms the universal scaling behavior.

Abstract

We consider the scaling behavior of directed percolation and of the pair contact process with a conjugated field. In particular we determine numerically the equation of state and show that both models are characterized by the same universal scaling function. Furthermore we derive the equation of state for the pair contact process within a mean-field approach which again agrees with the mean-field equation of state of the directed percolation universality class.