Seminarium Fizyki Wielkich Energii

The Standard Model of particle physics assumes that the interactions of the three charged leptons differ only because of their mass differences. Any deviation from this Lepton Universality Principle would suggest new kind of interactions or particles beyond the Standard Model.Precision tests of lepton universality have been performed over many years by many experiments.While results comparing processes involving electrons and muons seem to be in agreement with SM, recent studies involving the tau lepton show indications of the deviation from the Lepton Universality assumption. Recent results from the LHCb experiment will be reviewed.