NRQCD: A Critical Review

Abstract

In this talk I review some recent applications of NRQCD. I first discuss the unquenched NRQCD lattice extractions of the strong coupling constant, paying particular attention to the recent advances in reducing systematic errors. I then discuss the progress made in testing the NRQCD/factorization formalism for onium production. In particular, I gather the evidence, or lack thereof, for the universality of the production matrix elements. I also discuss the interesting question of polarized production, which is a crucial test of the formalism. I address the viability of this theory for the J/psi system as well as what needs to be done before we can reach any definitive conclusions.