Diffusion models are emerging as powerful tools for probabilistic prediction and inference in the physical sciences, but their application faces key challenges: high-dimensional state spaces, partial observability, and expensive simulations. In this talk, I present a unified diffusion-based framework addressing these issues across three complementary directions. First, latent-space diffusion...
Stage-IV surveys such as Euclid will deliver vast amounts of high-precision data, opening new opportunities to constrain cosmological models with unprecedented accuracy. A key step in this process is the reconstruction of the dark matter distribution from noisy weak lensing shear measurements. Current deep learning-based mass mapping methods achieve high accuracy, but either require retraining...
When the expansion rate of the Universe at recombination is used to infer the present expansion rate 𝐻0, the value derived in the ΛCDM model, 𝐻0 =67.4 km s−1 Mpc−1, is about in 6 𝜎 tension with the value measured locally, 𝐻0 =74 km s−1 Mpc−1. In this work, we consider instead the expansion history in the context of the symmetry of scale-invariant vacuum (SIV model). We first perform two major...
Galaxies are subject to intrinsic alignments, which correspond to the correlations between their 3D shapes and orientations and the underlying tidal field of dark matter across the large-scale structure of the Universe. This intrinsic galaxy alignment is traditionally measured with the two-point galaxy-density correlation function projected in the sky plane. However, the projection of 3D...
Cross-correlations between the thermal Sunyaev–Zel’dovich (tSZ) effect and tracers of large-scale structure provide a powerful probe of both astrophysics and cosmology. In this talk, I will present results on the cross-correlation of the tSZ signal with weak gravitational lensing and galaxy clustering in the context of the Euclid mission. These measurements allow us to study the distribution...
Neutral hydrogen (HI) intensity mapping with single-dish telescopes is a powerful probe of post-reionization cosmology, but extracting the signal is challenging due to bright foregrounds and realistic, frequency-dependent beam effects that degrade most standard methods. I present an evaluation of SDecGMCA, a spherical extension of GMCA that combines sparse component separation with explicit...
Next-generation radio interferometers, such as the SKA, will observe the radio sky with unprecedented sensitivity and resolution. Their wide sky coverage will also enable weak lensing studies using radio data. Radio weak lensing not only complements optical observations, but also allows access to higher redshifts. However, traditional shear estimation methods—based on measuring the ellipticity...
Neutral hydrogen intensity mapping encodes valuable non-Gaussian cosmological information, particularly at late times in the Universe’s evolution. Traditional two-point statistics, such as the angular power spectrum, are not sensitive to this information. In this work, we employ the starlet l1-norm, a multi-scale, higher-order statistic robust to instrumental effects to capture non-Gaussian...
