AVOIDED CRITICAL-BEHAVIOR IN A UNIFORMLY FRUSTRATED SYSTEM

We study the effects of weak long-ranged antiferromagnetic interaction s of strength a on a spin model with predominant short-ranged ferromag netic interactions, In three dimensions, this model exhibits an avoide d critical point in the sense that the critical temperature T-c(Q = 0) is strictly greater than lim(Q-->0) T-c(Q). The behavior of this syst em at temperatures less than T-c(Q = 0) is controlled by the proximity to the avoided critical point. We also quantize the model in a novel way to study the interplay between charge-density wave and superconduc ting order.