4 December 2025

3:25 PM – 5:00 PM

Amphi Grand Kursaal

Alain Riazuelo

Alain Riazuelo is a French astrophysicist specializing in cosmology and black hole physics. A former student of the École Polytechnique, he holds a Master’s degree in Astrophysics and Space Technology from the University of Paris XI. His training led him to explore the mechanisms of radio emission from pulsars and the evaporation of black holes. He defended his doctoral thesis at the University of Paris XI on the signature of primordial universe models in fossil radiation anisotropies, under the supervision of Nathalie Deruelle. He then completed postdoctoral fellowships at the University of Geneva, in Ruth Durrer’s group, and then at the CEA, continuing his research in theoretical cosmology. Since 2003, he has been a research fellow at the CNRS, assigned to the Institut d’Astrophysique de Paris, where he now holds the rank of first-class research fellow. His work focuses in particular on the formation of large structures, the cosmic microwave background, inflation, the topology of the universe, and topological defects. In addition to his research activities, he teaches regularly, notably at the University of Paris XI and the University of Geneva, in positions ranging from teaching assistant to assistant professor. Alain Riazuelo is also an author.

Where are the limits of intelligence and the intelligence of limits?

Does intelligence come up against insurmountable barriers, or is it just a perpetual movement of expansion and transcendence? This round table discussion explores the boundaries of knowledge and human, animal, and collective capabilities. Mathematician Cédric Villani explores the limits of understanding in mathematics, that universal language that sometimes stumbles upon the unprovable. Professor Grégory Ninot analyzes the limits of the body, between performance, resilience, and vulnerability. Ethologist Ludovic Dickel reveals how animal intelligence is constantly pushing back the boundaries we have imposed on it. Finally, astrophysicist Alain Riazuelo invites us to go beyond our cognitive abilities to “think the infinite.” Understanding our limits also means learning to overcome, transform, or accept them.