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Global Persistence in Directed Percolation

Klaus Oerding·Frederic van Wijland
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Abstract

We consider a directed percolation process at its critical point. The probability that the deviation of the global order parameter with respect to its average has not changed its sign between 0 and t decays with t as a power law. In space dimensions d<4 the global persistence exponent theta_p that characterizes this decay is theta_p=2 while for d<4 its value is increased to first order in epsilon = 4-d. Combining a method developed by Majumdar and Sire with renormalization group techniques we compute the correction to theta_p to first order in epsilon. The global persistence exponent is found to be a new and independent exponent. We finally compare our results with existing simulations.

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Klaus Oerding, Frederic van Wijland. 1998-05-05. Global Persistence in Directed Percolation. https://doi.org/10.1088/0305-4470%2F31%2F34%2F004

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