Backpropagating Verifier Rewards Through Continuous Flow Language Models
On the map: Diffusion models → Discrete and text diffusion also fits: Diffusion and flow policies for robotics
Abstract (arXiv)
Reinforcement learning (RL) has substantially improved the reasoning of autoregressive and discrete-diffusion language models. Language models that generate continuous token embeddings are emerging as a strong alternative, but RL post-training for them remains understudied. We propose method, a post-training framework for continuous flow language models. Such a model denoises token embeddings over multiple steps and decodes them into discrete tokens only at the last step. To obtain pathwise gradients, which backpropagate through continuous actions and have much lower variance than REINFORCE, we introduce a critic that estimates the value of intermediate token embeddings, bypassing the non-differentiable decoding step. The critic must also keep track of the value function as the policy changes; to this end, we design a critic that predicts a value from every token representation and improves policy optimization. Across four reasoning tasks, method reliably improves a continuous flow language model through RL post-training and outperforms baseline methods of the same type.
Key facts. No citing papers in the map yet (data through 14 Oct 2026). Placed in Discrete and text diffusion, one of 14 directions in Diffusion models. Builds on 42 of its 48 references that are in the map. First posted on arXiv 13 Oct 2026.
Builds on
42 of 48 references.
Closest ancestors · 6
Same direction, newest first
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- 2022DiffuSeq: Sequence to Sequence Text Generation with Diffusion Models17 Oct
Other references · 36
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