Strange line shapes and ECFL

Ever since high temperature superconductors have been known to scientists, they have been quite baffling. The central question is whether the standard textbook theories that we know and love already are applicable to describing these fascinating materials. The general sense is that those standard theories must be augmented to a great extent, if not replaced completely. Why this general sense? It is, of course, because of many puzzling experimental results that the standard textbook theories have a hard time explaining.