IBM Einstein Fellow
Xiao-Gang Wen is interested in gapped quantum many-body systems. He introduced topological order (1989) and SPT order (2009) to characterize them. Their boundaries have gravitational anomalies and/or symmetry anomalies. Their low-energy sector can have emergent (anomalous, higher, non-invertible) symmetries. Now, he is starting to work on gapless systems.