The normal state gap and other strange properties of cuprate superconductors

We summarise some of our recent work on the Normal State Gap(NSG) in hole-d oped high T-c cuprates, including an empirical model for the density of sta tes which appears to account for the effect of doping on the electronic ent ropy and spin susceptibility. Several features of our data such as the vari ations in entropy and thermoelectric power with hole content at room temper ature are consistent with numerical studies of the t - J model. We note tha t the effect of doping on the the thermoelectric power is difficult to reco ncile with the "stripes scenario". It is shown that the NSG strongly affect s most superconducting properties, and, via a simple tunnelling picture, th e out-of-plane resistivity and magnetoresistance in the normal state.