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arXiv · 1602.00642

Directed percolation process in the presence of velocity fluctuations: Effect of compressibility and finite correlation time

N. V. Antonov·M. Hnatič·A. S. Kapustin·T. Lučivjanský·L. Mižišin
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Abstract

The direct bond percolation process (Gribov process) is studied in the presence of random velocity fluctuations generated by the Gaussian self-similar ensemble with finite correlation time. We employ the renormalization group in order to analyze a combined effect of the compressibility and finite correlation time on the long-time behavior of the phase transition between an active and an absorbing state. The renormalization procedure is performed to the one-loop order. Stable fixed points of the renormalization group and their regions of stability are calculated in the one-loop approximation within the three-parameter $(\eps,y,η)$-expansion. Different regimes corresponding to the rapid-change limit and frozen velocity field are discussed, and their fixed points' structure is determined in numerical fashion.

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N. V. Antonov, M. Hnatič, A. S. Kapustin, T. Lučivjanský, L. Mižišin. 2016-01-14. Directed percolation process in the presence of velocity fluctuations: Effect of compressibility and finite correlation time. https://doi.org/10.1103/physreve.93.012151

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