GPT-6 Astra solved 49 of 50 unpublished theoretical-physics problems, and the experts' answer key turned out to be wrong
AspireAI community · arXiv (Chandra et al., ICTS / Google DeepMind / Harvard / KU Leuven)
Thirty-five physicists gave AI agents 50 unpublished theoretical-physics problems, and GPT-6 Astra solved 49 of them. The suite spans 11 subfields, from fluid dynamics to quantum field theory, and every answer is machine-checkable. On the track where agents could search the web, Astra in Codex got 49 of 50 at under $3 a problem. Opus 5.5 got 46, Gemini 3.8 Flash 34, open-weight DeepSeek 27 and GLM 21.
The part worth sitting with: several answers the physicists marked wrong turned out to be errors in the experts' own reference solutions.
Caveat: one pass per agent, and the authors say some contributors used AI while writing the problems.
https://arxiv.org/abs/2610.16733
Read the story and explore more from the AspireAI community.
Two sparse-autoencoder analyses have resisted scaling: matching semantically similar features across layers, and compressing large feature circuits into interpretable supernodes. This paper argues both are the same underlying problem, estimating semantic distances between SAE features that sit on different activation manifolds. Its representation treats each feature not as a single decoder vector but as an activation-weighted distribution over the hidden states expressing it, projects those distributions into a shared reference space, and compares them with Wasserstein distance. The representation is proved invariant to activation rescaling and stable under perturbation, and recovers true matches under finite-sample margin conditions. Empirically it outperformed decoder-vector and LLM-based baselines and captured subtle functional distinctions between related features, and it compressed large feature circuits into interpretable supernodes automatically. The limitation is that this is interpretability tooling: the paper demonstrates better feature matching and circuit compression, not that downstream interpretability claims become more accurate.