17.01.17 16:15
The mass discrepancy problem in galaxies: a missing gravity problem?
Benoit Famaey (Strasbourg)
In this talk, we review the observational evidence for an intimate connection between the baryonic surface density and the total gravitational field in galaxies. This observational fact presents a fine-tuning problem for the particle dark matter interpretation of mass discrepancies in galaxies. On the other hand, this is naturally explained within the Milgromian dynamics (MOND) paradigm, hypothesizing an effective breakdown of Newtonian dynamics in the extremely low acceleration regime. We present the current observational successes and failures of this approach, and a few theoretical undeprinnings which have been proposed to account for the MOND phenomenology in galaxies while preserving succesful predictions on the largest scales of the Universe.