https://doi.org/10.1140/epjqt/s40507-024-00232-2
Brief Report
Simulating 
lattice gauge theory with the variational quantum thermalizer
1
Institut für Theoretische Physik, Goethe-Universität, Frankfurt am Main, Germany
2
Science Laboratories, University of Durham, Durham, UK
Received:
3
August
2023
Accepted:
7
March
2024
Published online:
15
March
2024
The properties of strongly-coupled lattice gauge theories at finite density as well as in real time have largely eluded first-principles studies on the lattice. This is due to the failure of importance sampling for systems with a complex action. An alternative to evade the sign problem is quantum simulation. Although still in its infancy, a lot of progress has been made in devising algorithms to address these problems. In particular, recent efforts have addressed the question of how to produce thermal Gibbs states on a quantum computer. In this study, we apply a variational quantum algorithm to a low-dimensional model which has a local abelian gauge symmetry. We demonstrate how this approach can be applied to obtain information regarding the phase diagram as well as unequal-time correlation functions at non-zero temperature.
Key words: Hamiltonian lattice gauge theory / Quantum computing
© The Author(s) 2024
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