IU Professor, Radovan Dermisek, with students Keith Hermanek and Navin McGinnis, show in a recently published paper in PRL that the muon g-2 measurement can be explained by mixing of the muon with a 10,000 to 400,000 times heavier new lepton that has the same quantum numbers as the muon. Such mixing however slightly modifies other muon properties, namely how much it couples to the Higgs, Z and W bosons. They argue that these coupling modifications might be confirmed at the Large Hadron Collider or a future Linear Collider, but only in some cases. The definitive answer on ruling out this possibility will have to wait till the Future Circular Collider.
Reference: Radovan Dermisek, Keith Hermanek, and Navin McGinnis, Phys. Rev. Lett. 126, 191801