model architecture

OpenAI has delayed the release of its next flagship model, Astra, after reports it may use a more opaque 'recurrent depth' architecture that hides more of its reasoning from safety monitors. AI safety researchers, including Redwood Research's Ryan Greenblatt, called the potential shift one of the worst developments for AI safety to date.

Allen Institute for AI researchers conducted token-level analysis comparing their 7B-parameter Olmo 3 transformer and Olmo Hybrid models. The study finds hybrid architectures show a loss gap advantage of 0.04 on content words (nouns, verbs, adjectives) versus 0.02 on function words, while transformers match or exceed hybrids on repeated tokens and closing braces.