Fractionally Charged Particles at the Energy Frontier

The pattern in the Standard Model (SM) charges can be traced to an ambiguity in the gauge group of the SM. The easiest way to resolve this ambiguity would be to discover a particle with electric charge that is an integer multiple of e/6 (beyond +/- e, 0). The discovery of such fractionally charged particles would also challenge and potentially rule out many minimal unification models. In this talk I will review the connection between the `global structure' of the SM and the charges (color singlet) particles can have, then explore the phenomenology of fractionally charged particles, focusing on the constraints provided by current searches at the Large Hadron Collider (LHC). By reinterpreting existing results, we assess the bounds on various fractionally charged representations, uncovering scenarios where collider limits are unexpectedly weak or entirely absent.