Theoretical estimate(s) of the CP-violating quontity epsilon-prime/epsilon in K -> 2 pi decays

Abstract

I give a short presentation of the theoretical prediction of epsilon-prime/epsilon. Short distance and especially long distance aspects of the computation is discussed. I consentrate on the general framework and the chiral quark model approach, while other approaches are also shortly presented. Because of the intrinsic uncertainties of the long-distance computations, it is unlikely that new physics effects can be disentangled from the standard model prediction.