COSMIC VELOCITIES 2000: A REVIEW
J.A. WILLICK
Department of Physics, Stanford University,
Stanford, CA 94305-4060, USA

Abstract:
I review the status of cosmic velocity analysis as of January 2000, with an emphasis on two key questions: (1) What is the scale of the largest bulk flows in the universe? and (2) What is the value of $\beta\equiv\Omega_m^{0.6}/b$ indicated by cosmic velocities, and what does this tell us about $\Omega_m$ itself? These are the most important issues for cosmic flow analysis, and each has been controversial in recent years. I argue that a preponderance of the evidence at present argues against very large scale ($\simgt 100\,\hmpc$) bulk flows, and favors $\beta \simeq 0.4$--$0.5,$ corresponding to a low-density ($\Omega_m \simeq 0.2$--$0.3$) universe.