The Hirschfeld group studies problems of modern many-body theory associated with quantum materials. These are condensed matter systems that cannot be described by the conventional Bloch picture of a single electron moving in a periodic potential. They exhibit remarkable collective phenomena and novel ordered phases, and are expected to be relevant to the next generation of electronic devices. One particular focus is on "unconventional" superconductors, where electron pairing is driven by repulsive Coulomb interactions. Recently, a second focus has been opened on discovery of "extraordinary conventional" superconductors including developing high-throughput computational methods based on density functional theory descriptors.