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Numerical Study of a Field Theory for Directed Percolation

Ronald Dickman
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Abstract

A numerical method is devised for study of stochastic partial differential equations describing directed percolation, the contact process, and other models with a continuous transition to an absorbing state. Owing to the heightened sensitivity to fluctuationsattending multiplicative noise in the vicinity of an absorbing state, a useful method requires discretization of the field variable as well as of space and time. When applied to the field theory for directed percolation in 1+1 dimensions, the method yields critical exponents which compare well against accepted values.

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Ronald Dickman. 1994-07-12. Numerical Study of a Field Theory for Directed Percolation. https://doi.org/10.1103/physreve.50.4404

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