Quantitative phase diagrams of branching and annihilating random walks.

We demonstrate the full power of nonperturbative renormalization group methods for nonequilibrium situations by calculating the quantitative phase diagrams of simple branching and annihilating random walks and checking these results against careful numerical simulations. Specifically, we show, for the [see text] case, that an absorbing phase transition exists in dimensions d=1 to 6 and argue that mean-field theory is restored not in d=3, as suggested by previous analyses, but only in the limit d--> infinity.