When Agents “ Misremember” Collectively: Exploring the Mandela Effect in LLM-based Multi-Agent Systems - Xu, Naen; An, Hengyu; Shi, Shuo; Zhang, Jinghuai; Zhou, Chunyi; Li, Changjiang; Du, Tianyu; Fu, Zhihui; Wang, Jun; Ji, Shouling (International Conference on Learning Representations, 2026)