Simulating Reality: Understanding World Models in Artificial Intelligence

Following the rise of language models, a new stage in artificial intelligence is progressively emerging. While current systems excel at processing text and images, a key limitation remains: their difficulty in capturing the world in its physical, temporal, and causal dimensions

World models are part of this evolution. Their objective is to go beyond content generation by representing an environment, simulating its dynamics, and anticipating its evolution. 

This shift is significant, as it reflects a transition toward systems capable not only of responding to prompts, but also of reasoning about situations and their consequences. This direction is now at the core of numerous research initiatives and industrial developments. 

I. Definition and functioning: how world models change the paradigm 

A world model can be defined as an artificial intelligence system that builds an internal representation of the world in order to simulate its evolution

In practical terms, it is capable of: 

  • representing objects and states (position, movement, interactions), 
  • learning the transition rules governing these objects, 
  • predicting the consequences of an action over time. 

1. How does a world model function? 

In current architectures, notably described by Ha & Schmidhuber (2018), the system relies on three main components: 

  • perception module that transforms data (images, video) into compact representations, 
  • predictive memory that models the evolution of the environment over time, 
  • decision module that selects actions based on these predictions. 

The core mechanism is internal simulation. An agent can “imagine” multiple future scenarios, test actions virtually, and act based on the outcomes observed in this simulation.

2. A clear distinction from language models 

Comparing world models with current systems, particularly large language models (LLMs), helps clarify their specificity. 

LLMs are designed to predict sequences of words based on statistical patterns in textual data. By contrast, world models aim to integrate key dimensions of reality such as space, time, causality, and object interactions

In other words, a language model can produce a coherent description of a situation, whereas a world model seeks to simulate it and explore possible future trajectories. This distinction is particularly critical in contexts where systems interact with the physical world, such as robotics or autonomous mobility.

II. Origins and recent developments 

Research on world models follows a long trajectory, but recent developments have marked a significant acceleration. 

While early ideas date back to the 1990s, a major milestone came with the work of Ha & Schmidhuber (2018), demonstrating that an agent can learn a representation of the world, be trained in a simulated environment, and transfer its behavior to the real world. This principle of “simulation before action” is now a foundational concept. 

More recently, Yann LeCun has contributed to reviving the field. He argues that current systems, primarily focused on data prediction, remain largely reactive and lack a true world model enabling anticipation of consequences. His approach, notably through JEPA architectures, aims to predict abstract representations rather than raw data, bringing AI closer to a form of intuitive understanding of the world

At the same time, Fei-Fei Li highlights the emergence of spatial intelligence, emphasizing systems capable of understanding spatial relationships and interacting with physical environments. 

These developments point to a convergence: world modeling is becoming a central axis of AI evolution.

III. Current types of world models 

1. Interactive models 

Models such as Genie (Google DeepMind) or Muse (Microsoft) simulate playable environments where users or agents can act. Their main limitation lies in maintaining long-term coherence. 

2. 3D models 

3D models such as Marble (World Labs) generate immersive, navigable environments. However, they remain primarily focused on visual representation, with limited dynamic interaction. 

3. Physical models 

Systems like NVIDIA Cosmos or Wayve GAIA simulate real-world environments for autonomous driving or robotics. They can incorporate parameters such as weather, lighting, or traffic conditions, but often remain domain-specific and struggle to generalize. 

4. Video models 

Models such as Sora (OpenAI) or Veo (Google DeepMind) generate highly realistic videos from prompts or images, but without interactive capabilities. They depict a world rather than enabling scenario testing. 

5. Predictive models 

Approaches such as Joint Embedding Predictive Architecture (JEPA) aim to anticipate environmental evolution in an abstract space. They are promising for planning but remain insufficiently validated at scale.

IV. Opportunities: toward more anticipatory AI 

World models offer significant potential for AI systems interacting with the physical world. Their primary advantage lies in their ability to simulate scenarios before they occur. In fields such as robotics, autonomous mobility, and industry, they can enable testing of rare, dangerous, or costly situations without exposing real-world systems to risk. 

This simulation capability could also transform decision-making. Rather than reacting to immediate conditions, a world model can compare multiple trajectories and anticipate likely outcomes. This is particularly valuable in complex environments or for assisting robotic systems in physical tasks. 

Beyond operational use cases, world models have applications in science, industry, and creative sectors. They can simulate complex phenomena, generate interactive training environments, and analyze video streams to detect risks or anomalies. Their core promise is to enable AI systems capable of anticipation, virtual experimentation, and consequence-based reasoning

V. Risks and governance challenges 

1. Managing large-scale data collection 

World models rely on large volumes of data, including video, audio, and sensor data. This raises critical issues related to data protection, traceability, and usage limitations, particularly where identifiable or vulnerable individuals are involved. 

2. Preventing physical safety risks 

When embedded in robots or autonomous systems, prediction errors may lead to real-world consequences. Robustness, prior testing, human oversight, and scenario validation become essential requirements. 

3. Ensuring information integrity 

The ability to generate highly realistic environments and videos increases disinformation risks. Transparency mechanisms such as content labeling and traceability will be essential. 

4. Securing legal compliance 

Training these models may involve copyrighted content, image rights, or personal data. Organizations must ensure proper documentation of data sources, legal bases, and governance safeguards by design. 

5. Establishing democratic and ethical oversight 

World models may influence decisions in sensitive sectors such as mobility, healthcare, security, or defense. Their development requires transparent governance, impact assessment, and societal debate on acceptable uses

Conclusion: a promising yet uncertain evolution 

World models represent a major step toward AI systems capable of simulating, anticipating, and interacting with complex environments. They open significant opportunities, particularly for autonomous systems and real-world applications. 

However, these models remain under development. Their generalization capabilities, reliability, and regulatory oversight raise important challenges, especially in terms of data governance, safety, and compliance. 

Preparing your organization for the next generation of AI 

In this context, organizations must anticipate the emergence of these new AI architectures, which involve increased requirements in risk management, compliance, and system governance

At Naaia, we support companies and institutions in: 

  • identifying AI systems and emerging categories, 
  • mapping and classifying associated risks, 
  • implementing compliant governance frameworks. 

👉 Discover how the Naaia AIMS platform enables responsible AI adoption by combining governance, compliance, and operational efficiency.