ENERGY-LEVEL STRUCTURE OF 2-DIMENSIONAL SELF-INTERACTING RANDOM CHAINS

We study the energy level structure of the lowest-lying states for a two-dimensional version of the random chain model proposed by Iori, Marinari and Parisi. We find that the multifold degeneracy of the ground state is lifted as the random noise interaction is switched on and a solitary global minimum emerges in a glassy phase as the strength of the noise term is increased. This indicates that the model mimics the characteristics expected of a native protein. We also show that the transition from the globule state (with no noise term) to the glassy phase takes place smoothly.