Séminaire de Physique ThéoriqueThe dark matter conundrum
Benoît Famaey (L'Observatoire astronomique de Strasbourg)
Thursday 10 October 2019 14:00 - Tours - Salle 1180 (Bât E2)
In this talk, we review the dark matter conundrum, focusing on the current small-scale problems faced by the standard cosmological model. These problems might indicate that a better treatment of baryonic physics is still needed in simulations of galaxy formation in the cosmological context, or that something more fundamental is missing from our current picture. In particular, there is ample observational evidence for an intimate connection between the baryonic surface density and the total gravitational field in galaxies. We show why this observational fact still presents a problem for the collisionless dark matter interpretation of mass discrepancies at these scales, and we discuss the pros and cons of various alternatives.