AI models of unstable flow exhibit hallucination

ArXi:2604.20372v1 Announce Type: cross We report the first systematic evidence of hallucination in AI models of fluid dynamics, nstrated in the canonical problem of hydrodynamically unstable transport known as viscous fingering. AI-based modeling of flow with instabilities remains challenging because rapidly evolving, multiscale fingering patterns are difficult to resolve accurately. We identify solutions that appear visually realistic yet are physically implausible, analogous to hallucinations in large language models.