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Multicritical behavior in coupled directed percolation processes

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 نشر من قبل Uwe Taeuber
 تاريخ النشر 1997
  مجال البحث فيزياء
والبحث باللغة English
 تأليف Uwe C. Tauber




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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 beta^{(k)} which are markedly reduced at each hierarchy level k >= 2. We compute the fluctuation corrections to beta^{(2)} to O(epsilon = 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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