Astra developed the key ideas for two decade-old conjectures in just two hours. π±
@OpenAI @sama @gdb
On Sept 6, Xiangxin @NickZhou523786, Jiaxi, and I asked GPT-6-Astra to tackle Chen @wjmzbmr1 & Liβs 2016 best-arm identification conjectures. It produced the key algorithm and proof framework for resolving both in the independent, unit-variance Gaussian setting.
Claude Fable 5.1 cross-checked the proofs and found no issues. After preliminary human review, we formalized the main results in Lean 4, also with GPT-6-Astra, passing the kernel check on Sept 8.
On Sept 10, CodeBuddy + hy4-preview discovered that another team had posted a concurrent solution on arXiv (arxiv.org/abs/2609.10529v1) the day before (Sept 9). Our proof takes a different route, and we also provide Lean formalization code.
Manuscript + code:
github.com/zhouxiangxin1998/β¦
The way we do research may be changing faster than we expected.
Also thanks @thsottiaux for the reset :)
Thrilled to share our paper MiCRo: Mixture Modeling and Context-aware Routing for Personalized Preference Learning (arxiv.org/pdf/2505.24846) won an EMNLP 2025 Outstanding Paper Award! ππ
Huge congrats to the team @evangelinejy99 @RuiYang70669025 @YifanSun99 @FengLuo895614 @rui4research, and big thanks to our advisors Prof. Tong Zhang and @hanzhao_ml!
We introduce Gradient Variance Minimization (GVM)-RAFT, a principled dynamic sampling strategy that minimizes gradient variance to improve the efficiency of chain-of-thought (CoT) training in LLMs.
β Achieves 2β4Γ faster convergence than RAFT
β Improves accuracy on math reasoning benchmarks
β Generalizes to reinforcement learning methods such as GRPO
β Comes with theoretical convergence guarantees
π Paper: arxiv.org/abs/2505.02391
π Code: (expected in a few hours) github.com/RLHFlow/GVM
#LLM #MachineLearning #ReinforcementLearning #ChainOfThought #AIResearch








