Paper Overview
Field: Machine Learning Authors: Haoyu Zhou, Joe Watson, Anson Lei, Ingmar Posner Published: 2026-09-18 arXiv: 2609.22055
Motivation
A desirable property of a world model is the ability to learn continually across tasks—adapting to new environments without forgetting what the agent has already learned. The ability to retain and reuse knowledge from prior experience underpins efficient adaptation to novel environments, since the dynamics of the physical world can often be described by recurring mechanisms.
However, standard measures of adaptation entangle two abilities:
- The speed and capacity to learn unseen tasks
- The reuse of knowledge already acquired
- Each task curriculum is constructed by composing aspects of tasks already seen in the sequence
- Compositionality is factorized along the action axis and the perception axis, to better understand how different input modalities become bottlenecks for knowledge reuse
- State-of-the-art world models under classic continual learning approaches
- A modular world model whose dynamics backbone contains explicit reusable components
- Modular approaches achieve a better balance between knowledge reuse and forgetting than traditional continual learning methods
- No method fully resolves the problem, leaving clear open space for continual world models capable of "reuse without forgetting"
- arXiv: https://arxiv.org/abs/2609.22055
- Project website: https://object814.github.io/Compositional-Continual-Learning/
This happens because incoming tasks carry both novel content and recurring content, making it hard to tell whether a model is truly reusing prior knowledge.
Proposed Benchmark
To isolate knowledge reuse from prior experience, the authors propose a compositional continual learning benchmark for world models in robot manipulation: