Classification of 2+1D topological orders and SPT orders for bosonic and fermionic systems with on-site symmetries
Tian Lan, Liang Kong, Xiao-Gang Wen
Classified 2+1D gapped phases for bosons/fermions with any finite symmetry,
using three braided fusion categories E < C < M.
Symmetry protected topological orders and the group cohomology of their symmetry group
Xie Chen, Zheng-Cheng Gu, Zheng-Xin Liu, and Xiao-Gang Wen
Introduced group cohomology theory into condensed matter physics to describe
short-range entangled phases with symmetry for interacting bosons.
Emergence of helicity +/- 2 modes (gravitons) from qubit models
Zheng-Cheng Gu and Xiao-Gang Wen arXiv:0907.1203,
Nuclear Physics B online
Constructed two quantum spin models on a lattice which gives rise to emergent
gravitons (one with ω = k and the other with ω = k^3 dispersion).
Photons and electrons as emergent phenomena
Michael A. Levin and Xiao-Gang Wen Rev. Mod. Phys.77, 871-879 (2005),
String-net condensation provides a way to unify light and electrons.