Juniorprof. Dr. Marc Wagner
Lattice Gauge Theory
We are working in the field of theoretical particle physics and quantum field theory with particular focus on lattice gauge theory. Lattice gauge theory is a non-perturbative numerical technique to compute path integrals in gauge theories, in particular in QCD. It is, therefore, suited to determine QCD observables like hadron masses and decay constants from first principles, the QCD Lagrangian. All possible sources of systematic error (discretization errors, finite volume corrections, unphysically heavy up/down quark masses) can systematically be investigated and removed by means of controlled extrapolations.
In recent years it has become possible to simulate QCD with physically realistic setups including 2, 2+1 or 2+1+1 dynamical quark flavors, light up/down quark masses, which are close to or even at their physical value, large spacetime volumes to exclude finite volume effects and small values of the lattice spacing, to reliably perform continuum extrapolations. Numerical results obtained with such setups allow direct comparisons to experimental results and, consequently, to verify QCD up to experimental or numerical precision or, equivalently, to search for new physics. Alternatively, one can perform simulations in physical situations or for specific physical processes, where experiments are difficult to perform or currently even impossible, e.g. at very high temperatures. Finally, such simulations can help to get a better understanding of QCD, e.g. by investigating the structure of mesons or baryons or by computing interactions between quarks or between mesons and/or baryons.
Publications on arXiv.