15 Nov/22
16:00 - 18:00 (Europe/Zurich)

Massive QED on the lattice


Zoom at CERN

The current precision reached by lattice QCD calculations of low-energy hadronic observables, requires not only the inclusion of electromagnetic corrections, but also control over all the potential systematic uncertainties introduced by the lattice version of QED. We introduce a massive photon as an infrared regulator in lattice QED. That  produces a well defined theory, dubbed QEDM, amenable to numerical evaluation. The photon mass is removed through extrapolation. In this contribution we scrutinise aspects of QEDM such as the presence and fate of the zero modes contributions and we describe how such modes produce finite volume effects. We demonstrate that the required extrapolations are well controlled using numerical data obtained  (mostly) on two ensembles which only differ in volume.