Rich-Observation Reinforcement Learning with Continuous Latent Dynamics
Yuda Song, Lili Wu, Dylan J. Foster, Akshay Krishnamurthy
TL;DR
RichCLD addresses reinforcement learning with rich, high-dimensional observations and continuous latent dynamics by coupling representation learning with exploration. The core method, BCRL.C, learns a Bellman-consistent representation in the latent space, ensuring Lipschitz-structured backups, while CRIEE interleaves representation learning with exploration via discretization and optimistic planning. The authors establish statistical tractability under approximate coverability, prove a separation from weaker latent-Lipschitz notions, and demonstrate practical performance on visual maze and locomotion benchmarks with competitive latent representations and downstream rewards. This work advances sample-efficient learning in realistic settings where perception is rich and the latent dynamics are nonlinear and continuous, enabling more scalable RL for vision-based control tasks.
Abstract
Sample-efficiency and reliability remain major bottlenecks toward wide adoption of reinforcement learning algorithms in continuous settings with high-dimensional perceptual inputs. Toward addressing these challenges, we introduce a new theoretical framework, RichCLD (Rich-Observation RL with Continuous Latent Dynamics), in which the agent performs control based on high-dimensional observations, but the environment is governed by low-dimensional latent states and Lipschitz continuous dynamics. Our main contribution is a new algorithm for this setting that is provably statistically and computationally efficient. The core of our algorithm is a new representation learning objective; we show that prior representation learning schemes tailored to discrete dynamics do not naturally extend to the continuous setting. Our new objective is amenable to practical implementation, and empirically, we find that it compares favorably to prior schemes in a standard evaluation protocol. We further provide several insights into the statistical complexity of the RichCLD framework, in particular proving that certain notions of Lipschitzness that admit sample-efficient learning in the absence of rich observations are insufficient in the rich-observation setting.
