Intertwining Defects and Fermion-Boundary Scattering from TQFT

@misc{ohmori2026intertwining,
  title = {{Intertwining Defects and Fermion-Boundary Scattering from TQFT}},
  author = {Kantaro Ohmori and Masataka Watanabe and Pengcheng Wei and Yunqin Zheng},
  howpublished = {arXiv},
  year = {2026},
  month = oct,
  doi = {10.48550/arxiv.2610.31737},
  eprint = {2610.31737},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2610.31737},
  note = {CC BY 4.0},
}

TY  - UNPB
TI  - Intertwining Defects and Fermion-Boundary Scattering from TQFT
AU  - Kantaro Ohmori
AU  - Masataka Watanabe
AU  - Pengcheng Wei
AU  - Yunqin Zheng
PY  - 2026
DA  - 2026/10/22
PB  - arXiv
DO  - 10.48550/arxiv.2610.31737
UR  - https://arxiv.org/abs/2610.31737
AB  - We construct conformal boundary conditions of free Dirac fermions that preserve chiral, anomaly-free symmetries, and determine the associated fermion-boundary scattering, using the TQFT/CFT framework. We apply the construction to several previously unresolved examples: higher-charge monopoles in non-chiral QED, a family of SU(N)× SU(N+2)-symmetric models, the chiral QED with charges {1^5,3,(−2)^4}, and the charge-three monopole of the Standard Model. In these examples, out-going states are created by defect operators at the end of non-invertible topological lines; when such a line is non-simple, the out-going state splits into superselection sectors, and we give a formula for the branching ratios in terms of TQFT data. We also propose a general construction that adds and then gaps neutral spectators, under a technical assumption, which is potentially applicable to the 1-5-7-8-9 model.
ER  -