The discovery of neutrino masses is without any doubt one of the most exciting and celebrated advances in Particle Physics in recent years. The reason for this is twofold. Firstly, it constitutes the first solid evidence for physics beyond the Standard Model, and secondly, it opens the possibility of discovering new phenomena in future experiments. Even though a lot of work has been devoted lately to understand the origin and the implications of neutrino masses, these are still open questions awaiting answers.
Different theoretical arguments hinted to the possibility of neutrino masses well before they were experimentally discovered. Nevertheless, the actual values of the neutrino parameters turned out to be completely different to the expectations. Understanding why neutrino parameters are so different to the quark or charged lepton parameters is one of the most puzzling open problems in Particle Physics, and any theoretical study in this direction is certainly of great interest.
In addition, the discovery of neutrino masses demonstrates the violation of family lepton number in Nature and suggests the violation of total lepton number. Therefore, new phenomena are expected, such as the observation of lepton flavour violating processes or neutrinoless double beta decay. In the near future new experiments will search for these< phenomena with improved sensitivity and will hopefully find positive signals. On the other hand, if supersymmetry is realized in Nature, lepton flavour violating processes might also be discovered at the Large Hadron Collider (LHC), providing invaluable information about the physics responsible for flavour violation. It is then of utmost importance to evaluate the discovery potential of the new experiments and to develop strategies to understand the origin of neutrino masses in the light of all the new experimental results.
