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Multicritical behavior in coupled directed percolation processes

Uwe C. Täuber·Martin J. Howard·Haye Hinrichsen
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Abstract

We study a hierarchy of directed percolation (DP) processes for particle species A, B, ..., unidirectionally coupled via the reactions A -> B, ... When the DP critical points at all levels coincide, multicritical behavior emerges, with density exponents β^{(k)} which are markedly reduced at each hierarchy level k >= 2. We compute the fluctuation corrections to β^{(2)} to O(ε= 4-d) using field-theoretic renormalization group techniques. Monte Carlo simulations are employed to determine the new exponents in dimensions d <= 3.

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Uwe C. Täuber, Martin J. Howard, Haye Hinrichsen. 1998-01-20. Multicritical behavior in coupled directed percolation processes. https://doi.org/10.1103/physrevlett.80.2165

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