Theory Seminar: Variational approaches to Hamiltonian lattice gauge theory
Julian Bender (MPQ Theory Department)
Non-perturbative phenomena play a crucial role in the study of quantum field theories, since they appear e.g. in the low-energy sector of QCD (quantum chromodynamics), e.g. in the mechanism of confinement.
Julian Bender (MPQ Theory Department)
Theory Group Seminar Room B2.46
Wed 24. April 2021, 11: 30 am (MEZ)
Abstract:
Non-perturbative phenomena play a crucial role in the study of quantum field theories, since they appear e.g. in the low-energy sector of QCD (quantum chromodynamics), e.g. in the mechanism of confinement. As perturabtive series are not valid in these regimes, non-perturbative methods have been developed. One of the most prominent methods is lattice gauge theory, since the lattice allows a non-perturbative regularization of quantum field theories. Calculations are then usually carried out in the euclidean path-integral formalism, where expectation values can be evaluated by Monte-Carlo simulations. Although this technique has been extremely successful over the past decades, certain aspects are hard to capture in this framework, like real-time evolutions or finite chemical potentials. I will review the path-integral method to motivate and introduce the Hamiltonian formalism of lattice gauge theory. Afterwards, I will give an overview over the methods which can be used to study this Hamiltonian, with a particular focus on variational techniques.