论文精选

Mind Dreamer: 主动潜变量干预打破历史束缚,加速稀疏奖励强化学习

Mind Dreamer: Untethering Imagination via Active Latent Intervention on Latent Manifolds

精选理由

做强化学习稀疏奖励研究的团队终于有了突破历史束缚的新工具——Mind Dreamer 通过主动生成想象起点,大幅提升样本效率,建议跑过 DreamerV3 的开发者直接试。

AI 摘要

Mind Dreamer 提出一种名为主动潜变量干预(ALI)的框架,解决基于模型的强化学习中“历史束缚”问题——传统方法只能从观测状态开始想象,导致策略优化滞后于世界模型学习。它通过对抗生成器合成非连续的潜变量跳跃,探索物理可行但认知困难的盲点,并推导出中继价值函数和中继不确定性函数来分配跨空间断裂的信用。理论证明不确定性传播需要二次折扣,建立了形式化的认知视界。在DeepMind Control Suite上,Mind Dreamer 平均比 DreamerV3 快1.67倍,在稀疏奖励任务中加速达8.8倍。

原文 · arXiv: Google DeepMind

Mind Dreamer: Untethering Imagination via Active Latent Intervention on Latent Manifolds

Model-Based Reinforcement Learning (MBRL) leverages latent imagination for sample efficiency, yet remains constrained by Historical Tethering: imagination is typically initialized from observed states. This creates a learning asymmetry, where the world model's manifold discovery outpaces the policy's sparse-reward optimization. We propose Mind Dreamer (MD), a framework that operationalizes Active Latent Intervention (ALI) to transcend Markovian continuity. MD reformulates discovery as the minimization of a global Relay Manifold Expected Free Energy (R-EFE); by sampling initial states from a learned generator $s_0 \sim p_{gen}(\cdot)$ rather than the historical buffer, MD utilizes an adversarial generator to synthesize non-continuous latent jumps to epistemic blind spots that are physically plausible yet cognitively challenging. To resolve the credit assignment paradox across these spatial ruptures, we derive the Relay Value Function (RVF) and Relay Uncertainty Function (RUF). These potentials treat synthesized anchors as counterfactual intermediary states, propagating pragmatic and epistemic value through a principled Bellman-style formulation. Notably, we prove that uncertainty propagation across discontinuities necessitates a quadratic discount $γ^2$, establishing a formal epistemic horizon. Theoretically, MD approximates a variance-minimizing importance sampler that expands the manifold's spectral gap, reducing the hitting time to critical bottleneck states. Empirically, MD achieves a 1.67$\times$ average speedup over DreamerV3 on DeepMind Control Suite, reaching 8.8$\times$ in sparse-reward tasks.