Precision Cosmology: Successes and Challenges

After briefly reviewing the good agreement between large-scale observations and the predictions of the now-standard ΛCDM theory and problems with the MOND alternative, I summarize several of the main areas of possible disagreement between theory and observation: galaxy centers, dark matter substructure, angular momentum, and the sequence of cosmogony, updating earlier reviews [J. Primack, New Astronomy Reviews, 49 (2005) 25 and refs. therein; P. Coles, Nature 433 (2005) 248; V. Springel et al., Nature 440 (2006) 1147]. All of these issues are sufficiently complicated that it is not yet clear how serious they are, but there is at least some reason to think that the problems will be resolved through a deeper understanding of the complicated “gastrophysics” of star formation and feedback from supernovae and AGN.