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arXiv · 2105.14871

Subdiffusive Activity Spreading in the Diffusive Epidemic Process

Borislav Polovnikov·Patrick Wilke·Erwin Frey
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Abstract

The diffusive epidemic process is a paradigmatic example of an absorbing state phase transition in which healthy and infected individuals spread with different diffusion constants. Using stochastic activity spreading simulations in combination with finite-size scaling analyses we reveal two qualitatively different processes that characterize the critical dynamics: subdiffusive propagation of infection clusters and diffusive fluctuations in the healthy population. This suggests the presence of a strong-coupling regime and sheds new light on a longstanding debate about the theoretical classification of the system.

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Borislav Polovnikov, Patrick Wilke, Erwin Frey. 2021-05-31. Subdiffusive Activity Spreading in the Diffusive Epidemic Process. https://doi.org/10.1103/physrevlett.128.078302

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