SLEEC
The ANR SLEEC project aims to use self-supervised learning (particularly diffusion models) to make the most of the 21-cm cosmological signal that the SKA radio telescope will map starting in 2030. The goal is to optimize the statistics used to constrain cosmological and astrophysical models, and to go a step further by directly reconstructing the physical fields (density, temperature) that give rise to the signal. Ultimately, these two approaches could converge toward a true foundational model for 21-cm cosmology.
The project is led by Adélie Gorce at the IAS, in collaboration with Benoit Semelin of LUX (theParis Observatory | PSL) as a co-investigator. It is therefore shared between these two centers.
The Role of the IAS
The SLEEC project’s methodology is based on self-supervised learning, a family of AI techniques that learn to represent complex data without requiring manual labeling. In particular, the project relies on diffusion models, architectures that have demonstrated their power in capturing high-dimensional data distributions. The first research track will use “diffusion autoencoders” to construct compact representations of the three-dimensional 21-cm signal, seeking to minimize information loss while reducing sensitivity to astrophysical modeling uncertainties. The second research track will employ similar architectures to directly reconstruct the underlying physical fields (density, temperature) from the observed signal, an approach that is still emerging in the field. These methods will be coupled with Bayesian inference, notably through simulation-based inference, to produce robust constraints on the cosmological and astrophysical parameters of the reionization era. The project aims to validate these approaches using realistic simulations of the 21-cm signal, in anticipation of SKA data. Ultimately, combining these two research tracks could lay the groundwork for a foundational model dedicated to 21-cm cosmology—a reusable tool that can be applied to various future analyses.
Contacts
Advisors (scientific and technical)
- Adélie Gorce, Research Fellow and Co-Team Leader, Cosmology
Work Team
- Marian Douspis, Astronomer, Cosmology Team
- Lilian Crascall-Kennedy, Ph.D. Candidate, Cosmology Team
- Pietro Albanese Guidi, Ph.D. Candidate, Cosmology Group
