SYSTEMS WITH MULTIPLICATIVE NOISE - CRITICAL-BEHAVIOR FROM KPZ EQUATION AND NUMERICS

We show that certain critical exponents of systems with multiplicative noise can be obtained from exponents of the KPZ equation. Numerical s imulations in 1D confirm this prediction and yield other exponents of the multiplicative noise problem. The numerics also verify an earlier prediction of the divergence of the susceptibility over an entire rang e of control parameter values and show that the exponent governing the divergence in this range varies continuously with control parameter.