I am a condensed matter theorist, interested in the physics of materials with nontrivial electronic structure topology and in the observable effects of electron-electron interactions in condensed matter systems. Both electronic structure topology and electron-electron interactions may lead to macroscopic quantum phenomena, in which quantum mechanics manifests on macroscopic scales due to topology- or interaction-induced quantum coherence. Sometimes the two work in unison, as in fractional quantum Hall systems, in which case particularly interesting and unexpected phenomena result.