PU High Energy Theory Seminar

Abstract: The Schwinger model of two-dimensional quantum electrodynamics is among the oldest and best-studied quantum field theories, and is attracting renewed interest in connection with simulations of quantum lattice Hamiltonians. I will discuss an improved lattice formulation of the model, and show how it drastically increases the accuracy of various calculations. In particular, I will show how this lattice formulation in tandem with tensor network methods allows us to study the model with two flavors of Dirac fermions, and to obtain evidence towards the resolution of a 50-year-old question about its phase diagram. I will also give analytic results on the phase diagram and its relationship with the Berezinskii-Kosterlitz-Thouless transition, and discuss an analogy with CP-symmetry breaking in 4D QCD at θ = π.