Abstract

The ATLAS Collaboration recently reported the observation of quantum entanglement between top quarks. This constitutes the first observation of entanglement in a pair of quarks, and the observation of entanglement at the highest energy to date. Prompted by these results, I will illustrate recent developments in the field of quantum information theory in collider experiments, as this measurement paves the way to use colliders as a laboratory to study quantum information and other foundational properties of quantum mechanics. Furthermore, other similar measurements such as measuring quantum discord, reconstructing the quantum steering ellipsoid, and even establishing a violation of Bell inequalities, may be achievable at the LHC in the near future. From a high-energy physics perspective, borrowing concepts from quantum information theory inspires new approaches and observables that can be used to search new phenomena that may have escaped detection so far.