Speaker
Dr
Stefan Kuehn
(Perimeter Institute for Theoretical Physics)
Description
In recent years variational approaches based on efficient ansatzes for
the wave function of a quantum many-body system have proven their
power for addressing the Hamiltonian lattice formulation of gauge
theories. For one, methods based on Matrix Product States, a
particular kind of one-dimensional Tensor Network, have been
successfully applied to various Abelian and non-Abelian lattice gauge
models in $1+1$ dimension. Lately, we developed a variational ansatz
based on Gaussian States for $(1+1)$-dimensional lattice gauge
theories. These techniques do not suffer from the sign problem and
allow for addressing problems which cannot be tackled with
conventional Monte Carlo methods, such as out-of-equilibrium dynamics
or the presence of a chemical potential.
In this talk I will present some results demonstrating the
capabilities of these techniques using the Schwinger model and a
$(1+1)$-dimensional SU(2) lattice gauge theory as a test bench. In
particular, I will show that we can reliably simulate the static
aspects as well as the real-time dynamics of string breaking in these
models, and that these methods might be helpful for exploring
questions relevant for an implementation in (analog) quantum
simulators.