COLLECTIVE BEHAVIOR IN GLOBALLY COUPLED SYSTEMS CONSISTING OF 2 KINDSOF COMPETING CELLS

We investigate a model of globally coupled systems consisting of two k inds of competing cells subject to stochastic forcings. The problem of large numbers of coupled Langevin equations can be reduced to a simpl e problem of two-dimensional differential equations. The global variab les of the system show three types of collective phases: disordered ph ase, ordered steady phase, and coherent oscillation phase, and the tra nsition conditions between these phases can be accurately predicted in the thermodynamic limit. A stochastic resonancelike behavior in the c oherent oscillation output is revealed, and numerical simulations conf irm the analytical results satisfactorily.