About Me
Hello! I'm Matthew, a physicist with a passion for AI Safety and Interpretability. I do have other interests, such as tennis (I don't play) and running (I do). This website serves as a platform where I share my thoughts, research, and insights on topics that fascinate me.
Background
I have a background in accelerator physics, with particular interest in beam dynamics. Currently, I'm working as a physicist at UCLH (London, UK) where I engage in research projects that aim to improve the efficiency and quality of care for patients treated with radiotherapy.
Research Interests
My primary research interests include:
- Mechanistic Interptretability (whether that's the Pragmatic or Ambitious, or whatever else they want to call it)
- Monte Carlo related calculations (radiotherapy, radiation proteciton, accelerator design) and variance reduction techniques
- Statistical methods to simulate particle transport, e.g. Stochastic Differential Equations
Publications
My first-author publications:
- Southerby, M. et al. (2022). Multiobjective optimization and Pareto front visualization techniques applied to normal conducting rf accelerating structures. Physical Review Accelerators and Beams, 25(6), 062002. DOI
- Southerby, M. (2023). Beam Dynamics Studies and RF Cavity Design for Proton Radiotherapy Machines. PhD Thesis, Lancaster University.
- Southerby, M., & Apsimon, R. (2024). Beam Dynamics Framework Incorporating Acceleration to Define the Minimum Aperture in Two Focusing Schemes for Proton Radiotherapy Linac. arXiv:2403.10212. arXiv
- Southerby, M. et al. (2025). Fast SDE-based Monte Carlo dose calculation for proton therapy validated against Geant4. arXiv:2511.03115. arXiv
This Website
I created this site to document my learning journey and share insights with others who might find them useful. You'll find:
- Blog posts - Personal reflections, tutorials, and explorations of interesting topics
- Paper thoughts - Basic analysis of academic papers about AI Safety/Interpretability that I think are interesting (I am a hobbyist, not an expoert, so the discussion will be more elementary)
Get In Touch
I'm always interested in connecting with like-minded people. Feel free to reach out via my contact page.