Speaker
Description
The current precision reached by lattice QCD calculations
of low-energy hadronic observables, requires not only the introduction
of electromagnetic corrections, but also a control over all the potential
systematic uncertainties introduced by the lattice version of QED.
Introducing a massive photon as an infrared regulator in lattice QED, provides a
well defined theory, dubbed QED$_{\textrm{M}}$,
amenable to numerical evaluation.
An interesting feature of QED$_{\textrm{M}}$ is to provide a mass gap,
ensuring that finite volume corrections decay exponentially
with the linear size of the box. The photon mass is removed through
extrapolation. In this contribution we scrutinize aspects of
QED$_{\textrm{M}}$ such as the presence and
fate of the zero modes contributions and we describe
the determination of the photon mass corrections in finite and infinite volume.
We test our findings in a numerical feasibility study presented in the talk by J. Tobias Tsang.
