18 February 2020The Local Group, baryons, and the nature of dark matter

Mark Lovell

MPIA Heidelberg

It is well known that the number of Local Group galaxies is much smaller than the number density of dark matter haloes predicted by N-body cold dark matter simulations, and these same simulations often predict satellite central (<1kpc) densities higher than what we observe. Solutions to these problems include feedback from baryon processes, novel dark matter physics, and a combination of the two. In this talk I will review the status of baryon models, explain the likely impact of different dark matter candidates on the Local Group with a particular focus on the sterile neutrino, and present work comparing these models with observations.