Charged boson condensation in high-Tcsuperconductors

We explore the superconducting transition in the RVB (resonant valence bond) model, assuming that the superconductivity is due to a Bose-Einstein condensation of charged bosons in the RVB vacuum. It appears that the charged bosons behave like a weakly interacting $2+\epsilon$ dimensional boson gas and that the RVB superconductors exhibit many two-dimensional properties. Among others are a linear temperature dependence of the critical fields, which has already been observed in experiments, and a linear doping dependence of the transition temperature.