Simulating the absence of dark matter

摘要

Dwarf galaxies (DGs) have come to theforefront of astronomical research aspotential relics of the primordial Universeand as probes of galaxy evolution. It hasbeen suggested that DGs can form throughthe collapse of primordial matter within darkmatter haloes or through galaxy encountersdue to tidal forces removing gas and starsfrom the merging system (pictured). MoritzHaslbauer and collaborators show that twopopulations of DGs, corresponding to thesetwo formation pathways, naturally arise incosmological simulations but find that darkmatter-free tidal DGs should be very rare inthe local Universe.