Climbing NLO and NNLO Summits of Weak Decays

Abstract

I describe the history of the calculations of NLO and NNLO QCD corrections to weak decays of mesons and particle-antiparticle mixing in the period 1988-2010. Also existing calculations of electroweak and QED corrections to these processes are included in this presentation. These efforts bear some analogies to the climbing of Himalayas and various expeditions by several teams of strongly motivated _s15climbers_s15, acting mainly in Germany, Italy, Poland and Switzerland, allowed to move this field from the LO through the NLO to the NNLO level. The material is meant to be a guide to the rich literature on NLO and NNLO corrections in question and includes several anecdots related to the climbs that I was involved in. While, by no means this presentation should be regarded as a review of the size of NLO and NNLO corrections to weak decays, I hope that some of the comments made in the course of the presentation could turn out to be not only amusing but also instructive.