THE EFFECT OF NOISE ON PITCHFORK AND HOPF BIFURCATIONS

We present the results of an experimental and numerical investigation of the effects of noise on pitchfork and Hopf bifurcations. Good quant itative agreement is found between calculations and experiment. In the case of the pitchfork are find that natural imperfections override th e effects of the noise. However, novel noise amplification effects hav e been uncovered in the study of the Hopf bifurcation. These destroy t he critical event found in the noise-free case and could be of conside rable practical importance in systems containing dynamic bifurcations.