Saturday, April 04, 2009

MAMI and beyond, Day Five

Today's first talk was by Savely G. Karshenboim (Garching and St Petersburg) who spoke about hadron physics' impact on precision in atomic physics. Atomic physics is famously precise in its measurements, with relative precisions of order 10-12 now being achieved for some quantities. The largest uncertainty in theoretical predictions there now comes from uncertainty about the effects of nuclear and proton structure.

The second speaker was Wolfgang Gradl (Mainz) with a talk on hadronic uncertainties in flavour physics. Flavour physics is about quark-level quantities (CKM matrix elements), but only hadronic decay and oscillation processes are experimentally accessible; thus one needs good control of QCD effects contained in form factors, decay constants and the B meson bag parameter. Lattice QCD is an important ingredient here, in particular when coupled with effective field theories such as HQET.

This was followed by discussion sessions about the prospects for MAMI, about the prospects for an electron-nucleon collider, and about the impact of hadronic physics on high-energy physics. The good news for lattice theorists is that there is a high demand for precise lattice predictions by experimentalists. The not so good news is that most of that demand is in areas where the lattice is not in a position to make accurate predictions in the near future, such as resonances, hadronic scattering lengths or hadronic light-by-light scattering amplitudes.