Sakurai Prize Talk: Hunting New Animalcula with Flavor*

In 1676 Antoni van Leeuwenhoek discovered the Microuniverse populated by bacteria which he called animalcula (small animals). To this end he built microscopes with the resolution of 10^{-6} m. 348 years later after finding 12 years ago the last cornerstone of the Standard Model (SM) of particle physics, the Higgs particle, particle physicists search for new animalcula either directly with the help of high energy collisions or indirectly through quantum fluctuations causing certain rare processes with a change of quark flavor to occur at different rates than predicted by the SM. While the latter route is very challenging, requiring very precise theory and experiment, it allows the resolution of short distance scales as short as 10^{-21} m (Zeptouniverse) corresponding to energies of order 100 TeV or even shorter scales far beyond the reach of present high energy colliders. In fact in the coming flavor precision era, in which the accuracy of the measurements of rare processes and of the relevant theory calculations will be significantly improved, this goal could be reached. The main strategies for reaching this goal will be explained in simple terms including the most recent advances. We will summarize the present status of deviations from SM predictions for a number of flavor observables that give some hints for the existence of new animalcula responsible for these so-called anomalies.