${ϵ}^{\prime }/ϵ$: three years later

Abstract

Three years after the completion of the next-to-leading order calculation, the status of the theoretical estimates of ${ϵ}^{\prime }/ϵ$ is reviewed. In spite of the theoretical progress, the prediction of ${ϵ}^{\prime }/ϵ$ is still affected by a 100% theoretical error. In this paper the different sources of uncertainty are critically analysed and an updated estimate of ${ϵ}^{\prime }/ϵ$ is presented. Some theoretical implications of a value of ${ϵ}^{\prime }/ϵ$ definitely larger than $10^{-3}$ are also discussed.

Comments: 15 pages, 3 EPS figures, uses epsfig.sty. Invited talk to the 4th KEK Topical Conference on "Flavor Physics", KEK, Japan, 29-31 October 1996