High Temperature Superconductivity –

After 25 years, where are we at?

Michael Norman

Argonne National Laboratory

The field of high temperature cuprate superconductivity remains as controversial as ever.  Although certain matters have been settled, for instance the symmetry of the order parameter, there is no accepted microscopic framework for describing these materials.  This might seem surprising given their relatively simple electronic structure, but the issues involved touch some of the most fundamental ones facing physics - in particular the problem of how to properly treat strong correlations between electrons.  In this talk, I will discuss the progress that has been made, but also the many issues that will have to be resolved before we can say that we have "solved" the cuprate problem.