Top quark Physics and beyond: Quantum Observables at Colliders

A vast number of measurements exist in the top quark sector, spanning large, medium and tiny production cross sections of top quark pairs and single top quarks including associated productions of quarks and bosons. Ever more precise theoretical predictions are compared to data and challenge our understanding of the Standard Model, with effective field theory approaches allowing to discover new physics. An exciting new area in top quark physics is given by novel probes into quantum mechanics, i.e. quantum observables at colliders. In quantum mechanics, a system is said to be entangled (or even stronger correlated) if its quantum state cannot be described as a simple superposition of the states of its constituents. If two particles are entangled, we cannot describe one of them independently of the other, even if the particles are separated by a very large distance. When we measure the quantum state of one of the two particles, we instantly know the state of the other. The information is not transmitted via any physical channel; it is encoded in the correlated two-particle system. The talk will discuss recent exciting results in the top quark sector - including novel quantum observables - with data of the experiments at the Large Hadron Collider (LHC) at CERN. The talk concludes with perspectives into the bright future of high energy particle physics with an emphasis on quantum correlation measurements.