Luminous red galaxies in hierarchical cosmologies

Luminous red galaxies (LRGs) are much rarer and more massive than L * galaxies. Coupled with their extreme colours, LRGs therefore provide a demanding testing ground for the physics of massive galaxy formation. We present the first self-consistent predictions for the abundance and properties of LRGs in hierarchical structure formation models. We test two published models which use quite different mechanisms to suppress the formation of massive galaxies: the Bower et al. model which invokes active galactic nuclei (AGN) feedback to prevent gas from cooling in massive haloes and the Baugh et al. model which relies upon a superwind to eject gas before it is turned into stars.