NVIDIA Star Elastic: One Checkpoint, Three Reasoning Models, Zero-Shot Slicing.

NVIDIA released Star Elastic, a post-training method that nests three submodels (30B, 23B, 12B) inside a single Nemotron Nano v3 checkpoint. The technique uses only 160B tokens (360x reduction vs pretraining) and cuts memory for deploying all three from 126.1GB to 58.9GB in BF16. The clever bit: elastic budget control routes "thinking" through the smaller submodel and only uses the full 30B for the final answer. 16% accuracy gain at 1.9x lower latency. Accepted at ICML 2026.