@article{thewidthwallastrictexpressivityhierarchy,
  title = {The WidthWall: A Strict Expressivity Hierarchy for Hypergraph Neural Networks},
  author = {Fengqing Jiang and Yuetai Li and Yichen Feng and Kaiyuan Zheng and Luyao Niu and Bhaskar Ramasubramanian and Basel Alomair and Linda Bushnell and Radha Poovendran},
  year = {2026},
  eprint = {2605.13690},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2605.13690},
}