James Chok
Associate Researcher
University of NSW
University of NSW
J. Chok, M. Colbrook, M. Embree, and J. Fillman (2026). Contamination-free resolution of Cantor spectra and magic-angle localization in moiré quasicrystals and aperiodic media. Physical Review Letters [link]
J. Chok (2026). From Continuous Dynamics to Practical Gradient-Based Samplers. arXiv [link]
J. Chok, M. W. Lee, D. Paulin, and G. M. Vasil (2025). Divide, Interact, Sample: The Two-System Paradigm. arXiv [link]
September 2026 – Present · Research Associate, UNSW Sydney
Researching optimization, path planning, ocean forecasting, data assimilation, and reinforcement learning for maritime route optimization.
September 2022 – Present · PhD Candidate, University of Edinburgh
PhD thesis: Topics in Optimization, Sampling, Rational Function Approximation, and Operator Theory.
My research spans the mathematical foundations of optimization and sampling, rational approximation, operator theory, and high-performance scientific computing.
Teaching: High-Performance Computing for Mathematicians (PhD), Research Skills for Computational Applied Mathematics (MSc), Statistical Computing, and Python Programming.
August 2025 · Visiting Researcher, Nanyang Technological University, Singapore
Visited Dr Daniel Paulin to study Markov chain Monte Carlo methods for Bayesian modeling and extreme-value theory.
This collaboration resulted in the paper Divide, Interact, Sample.
September 2024 – August 2025 · Research Assistant, University of Cambridge
Worked with Dr Matthew Colbrook on spectral and fractal computations for twisted bilayer graphene, twisted bilayer Penrose quasicrystals, and Socolar quasicrystals.
This work resulted in the paper Cantor-Set Spectra in Moiré Quasicrystals and Beyond.
Led example classes for the Part III course Spectral Computations in Infinite Dimensions.
March 2020 – August 2022 · PhD Candidate, University of Sydney
Began my PhD in Applied Mathematics before transferring to the University of Edinburgh in 2022.
Researched polynomial-transform methods for improving the robustness of neural networks to adversarial attacks.
Teaching: Statistical Learning and Data Mining (MSc), Financial Time Series and Forecasting (MSc), Data Analytics for Business (MSc), and Mathematical Modelling.
March 2016 – December 2019 · BSc (Hons) in Applied Mathematics, University of Sydney
First Class Honours.