arXiv:cond-mat/9510099 · Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics

Nonuniversal critical spreading in two dimensions

Ronald Dickman

Published Mar 1, 1996• 27 citations

Abstract

Continuous phase transitions are studied in a two dimensional nonequilibrium model with an infinite number of absorbing configurations. Spreading from a localized source is characterized by nonuniversal critical exponents, which vary continuously with the density \ensuremath{\varphi} in the surrounding region. The exponent \ensuremath{\delta} changes by more than an order of magnitude and \ensuremath{\eta} changes sign. The location of the critical point also depends on \ensuremath{\varphi}, which has important implications for scaling. As expected on the basis of universality, the static critical behavior belongs to the directed percolation class. \textcopyright{} 1996 The American Physical Society.

DOI: 10.1103/physreve.53.2223

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