Quantum Simulation of Lattice Gauge Theories - Exploring fundamental physics in the era of quantum information

Gauge theories are ubiquitous in physics with applications ranging from fundamental high-energy physics(HEP) over emergent condensed matter phenomena to quantum information science and technology. Their study often requires non-perturbative numerical simulations and several regimes of interest remain inaccessible due to the numerical sign problem of Monte-Carlo simulations. Motivated by recent advances in the control of synthetic quantum systems QS-Gauge addresses the quantum simulation of lattice gauge theories (LGTs)beyond the reach of classical computations.Our objectives are (i) to establish a class of regularized gauge theories co-designed for quantum simulation, enabling (ii) the construction of digital quantum algorithms tailored to “LGT-aware” hardware, and (iii) to analyze paradigmatic phenomena such as confinement using classical tensor network (TN) simulations which serve as benchmarks for quantum devices.QS-Gauge is based on an unconventional generalization of the well-established Kogut-Susskind Hamiltonian formulation of LGTs, where the defining non-abelian Lie algebra is deformed to a quantum group. The resulting theories are related to string-net models employed for the classification of topological order in condensed matter which we will leverage to adapt TNs to HEP applications. As these truncated non-abelian LGTs are efficiently represented as multi-level systems, we pursue the development of quantum algorithms for qudits instead of qubits as elementary information carriers. In close collaboration with experimental colleagues and in synergy with the development of early fault-tolerant hardware, we focus on trapped-ion qudit quantum computers and fermionic alkaline-earth Rydberg atoms for optimized (fermion-)qudit architectures. Our results are expected to have far-reaching interdisciplinary impact and inform the development of future quantum devices, also for condensed matter physics, quantum chemistry and general quantum information processing.