Part II: World Models¶
World models are learned representations of how the world works — capturing the dynamics, structure, and regularities of an environment. They enable agents to predict, plan, and imagine without direct interaction, forming a critical component of intelligent embodied systems.
What You'll Learn¶
This section covers:
- What Are World Models? — Definitions, motivations, and the cognitive science perspective
- Representation Learning — How to learn useful latent spaces for world modeling
- Video Prediction — Predicting future visual observations
- Planning with World Models — Using learned models for decision-making
- Foundation World Models — Large-scale, general-purpose world models
- Key Papers — Essential reading in world models
Why World Models?¶
The motivation for world models comes from multiple directions:
- From RL: Model-based RL is 10-100x more sample-efficient than model-free approaches
- From cognitive science: Humans constantly simulate the world mentally to plan and predict
- From robotics: Real-world interaction is expensive; simulation with learned models is cheap
- From scaling: Foundation world models are emerging as a path to general-purpose physical reasoning
Connection to Other Parts¶
graph LR
MB[Model-Based RL<br/>Part I] --> WM[World Models<br/>Part II]
WM --> EA[Embodied AI<br/>Part III]
WM --> DR[Distributed RL<br/>Part IV]
EA -->|data for<br/>training| WM
- Part I (RL): World models generalize the dynamics models from model-based RL
- Part III (Embodied AI): World models enable sim-to-real transfer and robot learning from imagination
- Part IV (Distributed RL): Training large world models requires distributed systems