Neutrinos as a Window to New Physics

<!--HTML--><p>We discuss some of the manifold ways in which physics beyond the Standard Model (SM) can manifest itself in the neutrino sector. We begin with the dimension-4 "neutrino portal" which leads to mixing between SM neutrino and any new singlet fermion. In this context, we highlight recent insights into the observed neutrino oscillation anomalies, both within the SM and beyond. At dimension-5, we introduce neutrino magnetic moments as a discovery tool for TeV-scale new physics, and we discuss the various terrestrial, astrophysical, and cosmological constraints on such operators. Finally, we consider dimension-6 operators involving neutrinos in the context of Standard Model Effective Theory (SMEFT) and its lower-energy counterparts. We demonstrate that experiments observing LHC neutrinos, such as FASERν and SND@LHC, will become interesting players in the future.</p> TH colloquia: https://cern.zoom.us/j/67346292748?pwd=ZnRkQWh0ZXVFQTc5K256QW5NcEcrdz09