What: Astrophysics Colloquium

When: Sept 16th, 2026, 14:00-15:00 CEST 

Where: Aula Galilei, ground floor, Edificio C, Area Pontecorvo

Speaker:  Prof. Roberto Maiolino, University of Cambridge

Title: Early galaxies and infant black holes in the distant Universe

Abstract: With the advent of the James Webb Space Telescope, the past few years have been truly transformational for our understanding of the distant Universe, yielding a plethora of unexpected and groundbreaking results. These include the discovery of very luminous galaxies within the first few hundred million years after the Big Bang, often exhibiting peculiar chemical enrichment patterns, and indications for the first generation of stars. Equally compelling is the identification of a large, previously unknown population of massive black holes in the early Universe, with properties that differ significantly from those of their counterparts at later cosmic epochs. I will provide a brief overview of these discoveries and discuss how they are reshaping our understanding of the formation and evolution of galaxies and black holes in the early Universe.

What: Astrophysics Colloquium

When: May 18th, 2026, 16:00-17:00 CET

Where: Building C - Room 248 (first floor)

Speaker: Prof. Miguel Á. Sánchez-Conde, Universidad Autónoma de Madrid

Title: Searching for dark matter in a clumpy universe

Abstract: Dark matter halos in the standard LCDM model contain abundant substructure, or subhalos, which are crucial for indirect dark matter searches through annihilation signals. The most massive subhalos host dwarf galaxies, currently prime targets, while smaller dark subhalos may also provide excellent opportunities due to their proximity and high dark matter content. Moreover, the clumpy distribution of subhalos enhances the overall annihilation signal. This talk will present numerical work on Milky Way–like subhalo populations and discuss their impact on gamma-ray dark matter search strategies with instruments such as Fermi LAT, MAGIC, and CTAO, including recent searches and derived constraints.

What: Astrophysics Colloquium

When: Mar 30th, 2026, 16:00-17:00 CET

Where: Building C - Room 131 (ground floor)

Speaker: Dr. Michele Ginolfi, University of Florence

Title: Decoding Galaxy Properties with Machine Learning and Simulation-Based Inference

Abstract: The era of large-scale astronomical surveys demands innovative approaches for the rapid and accurate analysis of vast spectral datasets. A promising direction to address this challenge lies in the synergy between physics-based simulations and machine learning. Astronomy, like many other scientific disciplines, relies heavily on simulations to encode our physical understanding of complex processes, generate hypotheses, design experiments, and explore causal relationships. Increasingly, this knowledge is embedded in forward models that produce realistic synthetic spectra, images, and data-cubes. A central and long-standing challenge, however, is the solution of the "inverse problem": inferring the underlying physical parameters from observational data. In this talk, I will present a powerful framework to tackle this problem based on simulation-based inference (SBI) accelerated by invertible neural networks. Thanks to their amortised nature, these methods offer significant advantages over traditional Bayesian approaches: once trained, they enable fast inference and naturally yield complex, multi-modal posterior distributions conditioned on observables. I will show  preliminary results based on simulated spectra for upcoming instruments, along with ongoing SBI applications aimed at probing the interstellar medium in galaxies. Finally, I will discuss key open challenges, including model interpretability and domain adaptation, with particular emphasis on bridging the gap between synthetic training data and real observations.