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Eye on AI Weekly Research Watch
Craig Spencer Smith
NeutronGym: Physics-Graded Neutron Instrument Design for LLM Agents
OCT 7, 20262 MIN
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Description
Instrument design tests whether language-model agents can apply physics rather than recall it. NeutronGym is an executable environment for neutron instrument design: agents build instruments through validating tools, McStas ray-traces them, and a graded ladder scores syntax, runtime, structure, and science without an LLM judge. Seven frontier models reproduce at most 7 of 16 published instruments. RL on its reward lifts Qwen3-8B from 11% to 77% on held-out instances, surpassing an untrained Qwen3-32B.
Authors: Lijie Ding, Changwoo Do
Paper: https://arxiv.org/abs/2610.03631v1

