Hubert Spiesberger - Low-Energy Electron Proton Scattering at MESA

Recent technical developments will make it possible to perform high-precision measurements of polarized electron proton scattering at low energies. The P2 experiment at the Mainz Energy-Recovering Superconducting Accelerator aims to measure the weak charge of the proton allowing to extract the weak mixing angle to a precision of 0.15% and to limit non-standard 4-fermion interactions up to a mass scale of 50 TeV. I will describe the theory challenge to obtain accurate predictions for this measurement.