What did we learn in theory from the $\Delta A_{CP}$-saga?

Abstract

The measurement of CP violation in the charm sector triggered a lot of theoretical activities and re-considerations. Nevertheless currently neither theory nor experiment have reached definite conclusions about the origin of a large CP violating effect in hadronic $D$ decays. We review briefly (part of) the current theory literature and present as the most important outcome of the many investigations initial steps in a long journey to understand the standard model contribution to hadronic $D$ meson decays from first principles as well as various control channels, that can be studied by experiment.

arXiv commentto appear in the proceedings of The 6th International Workshop on Charm Physics (CHARM 2013)