Cold-atom quantum simulators of gauge theories

Gauge theories constitute the basis of the Standard Model and provide useful descriptions of various phenomena in condensed matter. Realizing gauge theories on tunable tabletop quantum devices such as cold-atom quantum simulators offers the possibility to study their dynamics from first principles and to probe effects that are out of reach of dedicated particle colliders, such as deviations from gauge invariance. These quantum simulators can potentially provide insights into high-energy and nuclear physics questions, while also serving as a versatile tool for the exploration of topological phases and ergodicity-breaking mechanisms relevant to low-energy many-body physics. Recent years have seen substantial progress in the implementation of (1 + 1)D Abelian gauge theories using ultracold atoms. In this Review, we chronicle these advances, highlighting key developments in stabilizing gauge invariance and scaling up from basic building blocks to large-scale realizations where gauge-theory phenomena can be probed. We offer an outlook on future directions and the requirements for advancing this technology to the next level. Large-scale quantum simulations of gauge theories are relevant to high-energy and condensed matter physics. This Review covers recent developments in simulating lattice gauge theories using cold atoms.