GEOPHYS: The Geometry of Physical Plausibility

Christian Internò; Alexander Pondaven; Habon Issa; Fabio Pizzati; Francesco Pinto; Markus Olhofer; Ivan Laptev; Philip Torr; Eero P. Simoncelli; Barbara Hammer; David Klindt

arXiv · 2606.20707

GEOPHYS: The Geometry of Physical Plausibility

Christian Internò·Alexander Pondaven·Habon Issa·Fabio Pizzati·Francesco Pinto·Markus Olhofer·Ivan Laptev·Philip Torr·Eero P. Simoncelli·Barbara Hammer·David Klindt

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Abstract

While humans can identify physically implausible events within milliseconds, machine learning approaches addressing the same problem are extremely slow and expensive. They either rely on external multimodal-LLM judges or require ad-hoc modifications to the training procedure. In this work, we argue that indicators of physical plausibility are implicitly captured by five geometric properties of the per-frame embeddings produced by frozen image encoders. In aggregate, we call them GEOPHYS. First, we show that these signals correlate with human EEG responses to two forms of object-permanence violations. Second, GEOPHYS robustly discriminates physically implausible videos from realistic ones, achieving state-of-the-art physics-violation detection: 98.3% on LikePhys and 93.3% on IntPhys2, whereas V-JEPA 2, GPT-4o, Gemini, and twelve modern video diffusion models perform near chance. Third, used as a best-of-N verifier for physical alignment during video generation, GEOPHYS lifts MAGI-1 24B from 50.01% to 64.50% on PhysicsIQ at 1.5x lower wall-clock and 4.65x lower memory than the V-JEPA 2 world-model verifier. Ultimately, GEOPHYS demonstrates that physical plausibility in videos can be assessed by leveraging the emergent geometric properties of temporal features extracted from image encoders.

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Christian Internò, Alexander Pondaven, Habon Issa, Fabio Pizzati, Francesco Pinto, Markus Olhofer, Ivan Laptev, Philip Torr, Eero P. Simoncelli, Barbara Hammer, David Klindt. 2026-06-15. GEOPHYS: The Geometry of Physical Plausibility. https://arxiv.org/abs/2606.20707

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