VidPhysOracle: Benchmarking Video World Models Against Physically Grounded Futures

Recent video generation and world models can synthesize visually compelling futures, yet their ability to capture real-world physics remains unclear. Existing physics evaluations largely rely on hand-crafted rules or learned judges, requiring the evaluator to infer what should physically happen. We introduce VidPhysOracle, a benchmark and physically grounded video dataset that evaluates generated futures against oracle trajectories produced by physical simulation. Rather than asking whether a video merely looks physically plausible, VidPhysOracle measures how closely its dynamics match a known physical evolution.The dataset covers diverse rigid-body, deformable/soft-body, and fluid systems with controlled initial conditions and corresponding simulated futures. To reduce the simulation-to-real visual gap, we construct physics-preserving photorealistic videos through appearance transformation while retaining the underlying geometry and motion. We further introduce a reference-based unified physical consistency score to quantify dynamic agreement beyond pixel-level similarity, and benchmark seven representative open-source video and world models under identical initial conditions.Beyond evaluation, VidPhysOracle provides physically valid future trajectories for physics-aware fine-tuning and post-training, enabling existing video models to improve physical consistency. Overall, VidPhysOracle offers a unified framework for evaluating, diagnosing, and improving the physical capabilities of video world models.