Approximation for directed percolation in d=1+1.
We introduce an approximation specific to a continuous variable formulation of directed percolation, which is strictly equivalent to (1+1)-dimensional directed bond percolation. We find that the critical exponent associated with the order parameter (percolation probability) is beta=(1-1/square root[5])/2=0.276 393 202 em leader, in remarkable agreement with the best current numerical estimate beta=0.276 486(8).
Sire
Clément
C
Laboratoire de Physique Quantique (UMR 5626 du CNRS), Université Paul Sabatier, F-31062 Toulouse Cedex 4, France. Clement.Sire@irsamc.ups-tlse.fr