Speaker: Mauricio Bustamante, Center for Cosmology and AstroParticle Physics (CCAPP), The Ohio State University
Abstract: High-energy astrophysical neutrinos, recently discovered by IceCube, are fertile ground to test for the presence of new physics. We can look for it at previously unexplored energies -- from tens of TeV to a few PeV, far beyond the reach of laboratory experiments. Due to cosmological-scale baselines -- Mpc to Gpc -- tiny new-physics effects, otherwise unobservable, could, by accumulation, become detectable. These include neutrino decay, violation of fundamental symmetries, and novel neutrino-neutrino interactions. I will show that the spectral features and flavor composition of neutrinos can reveal the presence and type of new physics. I will give special attention to neutrino decay. Present-day data are already sensitive to some models. More statistics, improvements in detection techniques, and detector upgrades will only enhance the sensitivity.