Dorota M. Grabowska, University of Washington

Hamiltonian lattice gauge theories carry a large redundancy, and most of the Hilbert space used to represent them is unphysical. The usual approach keeps that redundancy, starts in a physical state, and relies on penalty terms or symmetry checks to keep noise from driving the simulation out of the physical subspace. This talk argues that removing the redundancy outright, by gauge fixing, is sometimes advantageous. Fixing the gauge along a maximal tree leaves only physical degrees of freedom, so every state on the register is a physical state. This changes the structure of the Hamiltonian in ways that can be put to use, from choosing bases suited to different coupling regimes to making some conceptually subtle questions about a theory directly accessible. The talk discusses what gauge fixing costs, what it gains, and the phenomena it makes easier to identify and study.