Martin Sahlén

Martin Sahlén is an Associate Professor in the Department of Physics and Astronomy at Uppsala University, specializing in astronomy with a focus on astrophysics. His research spans theoretical and observational studies of the large-scale structure of the universe through galaxy clusters, voids, and the universe's first galaxies to understand galaxy physics, star formation, dark energy, dark matter, cosmic inflation, and the reionization process in the early universe.

Dr. Sahlén's research interests center on cosmology, particularly the intersection of theoretical models and observational data. He employs Bayesian inference techniques to analyze cosmological datasets, with special attention to the philosophy of cosmology, including model inference, fine-tuning of natural constants, and multiverse explanations. His work bridges observational astronomy with theoretical physics to address fundamental questions about the universe's structure and evolution.

His recent publications (2024-2025) predominantly focus on the Euclid space mission, representing a major portion of his scholarly output. These works span instrumentation, data analysis techniques, cosmological simulations, and theoretical interpretations. Key themes include constraints on modified gravity models, galaxy cluster analyses, weak lensing studies, and machine learning applications for extracting physical parameters from astronomical data. His research demonstrates a consistent focus on leveraging next-generation observational data to test fundamental cosmological theories.

Dr. Sahlén serves as Principal Investigator for multiple significant research grants, including: (1) 'The Galaxy – Dark Matter Connection with HST, JWST and EUCLID' (2021-2026, 8 MSEK); (2) 'Searching for New Physics in the Early Universe' (2022-2024, 1 MSEK); and (3) 'Astronomical object classification and anomaly detection with complex spectroscopic 4MOST data sets' (2023-2027, 4 MSEK). He actively participates in major scientific collaborations including 4MOST, BUFFALO, Euclid and SKA Observatory, and contributes externally to the Dark Energy Survey.

As an educator, Dr. Sahlén is responsible for and teaches the interdisciplinary course 'Three Approaches to Cosmology' (10 credits), which likely reflects his broad expertise spanning observational, theoretical, and philosophical aspects of cosmology.