Publication Type
PhD Dissertation
Version
publishedVersion
Publication Date
5-2026
Abstract
My goal is to build autonomous systems that expand the reach of human capability in challenging domains such as undersea and space exploration, disaster response, and large-scale infrastructure. In everyday settings, these systems will increasingly appear in safety-critical applications such as autonomous driving, robotics, and industrial manufacturing. A central requirement for these systems is the ability to operate reliably under uncertainty, particularly when the environment behaves in unanticipated ways.
The robust handling of unforeseen environment dynamics is therefore a technical cornerstone of autonomous decision-making; Adversarial attacks provide a useful and principled lens through which to study this problem. Adversarial \textit{robustness}, then, is both a practical starting point and a meaningful objective in its own right, particularly for systems deployed in safety-critical settings.
In this thesis, I establish a new foundation for adversarial reinforcement learning, motivated by the comparative structure of regret. Existing approaches to robustness typically rely on adversarial training, which often fails to generalize to novel attacks, or worst-case optimization, which provides lower-bound guarantees but tends to produce overly conservative policies. To address these limitations, I propose a framework guided by three key principles. First, robustness should be evaluated at the trajectory level, ensuring stability over long sequences of decisions rather than individual actions. Second, robust agents must be designed with future adversaries in mind, rather than optimized against a fixed perturbation strategy. Finally, principled descriptions of the underlying problem structure are essential: methods that exploit the true structure of adversarial decision-making remain robust as applications evolve, while purely heuristic approaches often prove brittle.
Building on these principles, this dissertation develops scalable regret-based formulations of robustness, analyzes the structural role of partial observability in adversarial reinforcement learning, and demonstrates their effectiveness on both standard benchmarks and real-world applications.
Keywords
Robust Reinforcement Learning, Reinforcement Learning, Adversarial Reinforcement Learning, LLM Red Teaming
Degree Awarded
PhD in Computer Science
Discipline
Artificial Intelligence and Robotics
Supervisor(s)
VARAKANTHAM, Pradeep Reddy
First Page
1
Last Page
125
Publisher
Singapore Management University
City or Country
Singapore
Citation
BELAIRE, Roman Lok-Ming.
Sequential Robustness in Adversarial Reinforcement Learning. (2026). 1-125.
Available at: https://ink.library.smu.edu.sg/etd_coll/909
Copyright Owner and License
Author
Creative Commons License

This work is licensed under a Creative Commons Attribution-NonCommercial-No Derivative Works 4.0 International License.