Matthijs Mars

I am Matthijs, a postdoctoral researcher at Leiden University working on the application of machine learning techniques to high contrast imaging for direct imaging of exoplanets. Prior to this, I completed my PhD through the College for Doctoral Training in Data Intensive Science at UCL’s Mullard Space Science Lab, where I worked with Jason McEwen and Marta Betcke on developing innovative machine learning approaches for astronomical imaging.

My doctoral research focused on advancing image reconstruction methods for radio interferometry, a crucial tool in astronomy used to study phenomena from the epoch of reionisation to cosmic magnetism and distant galaxies. With next-generation telescopes like the Square Kilometre Array (SKA) set to generate unprecedented volumes of data, my work addressed the pressing need for efficient and scalable reconstruction techniques. I developed two novel approaches: a fully data-driven method and a hybrid approach combining data-driven learning with model-based optimization. These methods were initially developed for SPIDER, an optical interferometer concept, before being extended to radio interferometry.

A key challenge I tackled was adapting these learned reconstruction methods to handle the varying visibility coverages inherent in radio interferometry, developing robust training strategies that made the models coverage-agnostic. I also integrated these approaches into a generative framework capable of quantifying uncertainties in the reconstructions – a crucial feature for scientific interpretation. The resulting methods demonstrated significant improvements in both computational efficiency and reconstruction quality compared to traditional approaches, enabling real-time imaging for SPIDER and offering efficient, high-quality reconstructions with uncertainty quantification for radio interferometric telescopes.

During my PhD, I also collaborated on several other projects. I worked with Spotify to enhance their podcast dataset by precomputing audio features for the TREC Podcast track, a data challenge focused on information retrieval from podcasts. Additionally, I spent 6 months at the STFC Hartree Centre developing deep reinforcement learning methods for controlling plasma shape in nuclear fusion reactors, under the supervision of Adriano Agnello, George Holt, and Nicola Amorisco.


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Talks and Posters