On the critical behavior of the Susceptible-Infected-Recovered (SIR) model on a square lattice

Tânia Tomé; Robert M. Ziff

doi:10.1103/physreve.82.051921

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arXiv · 1006.2129

On the critical behavior of the Susceptible-Infected-Recovered (SIR) model on a square lattice

Tânia Tomé·Robert M. Ziff

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Abstract

By means of numerical simulations and epidemic analysis, the transition point of the stochastic, asynchronous Susceptible-Infected-Recovered (SIR) model on a square lattice is found to be c_0=0.1765005(10), where c is the probability a chosen infected site spontaneously recovers rather than tries to infect one neighbor. This point corresponds to an infection/recovery rate of lambda_c = (1-c_0)/c_0 = 4.66571(3) and a net transmissibility of (1-c_0)/(1 + 3 c_0) = 0.538410(2), which falls between the rigorous bounds of the site and bond thresholds. The critical behavior of the model is consistent with the 2-d percolation universality class, but local growth probabilities differ from those of dynamic percolation cluster growth, as is demonstrated explicitly.

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Tânia Tomé, Robert M. Ziff. 2010-06-10. On the critical behavior of the Susceptible-Infected-Recovered (SIR) model on a square lattice. https://doi.org/10.1103/physreve.82.051921

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